Category Archives: Gene Medicine

LEXINGTON, Ky. If youve just never been able to wrap your mind around how people eat vegetables like broccoli or brussels sprouts and actually enjoy the taste, it turns out you may be experiencing an entirely different taste when you bite into a forkful of greens. According to a new set of preliminary research, some people carry a specific gene that makes certain foods, including most heart healthy vegetables, taste especially bitter.

Those carrying this taste gene are much more likely to have a harder time incorporating vegetables into their daily diets.

Your genetics affect the way you taste, and taste is an important factor in food choice, says study author Jennifer L. Smith, a postdoctoral fellow in cardiovascular science at the University of Kentucky School of Medicine in Lexington, in a release. You have to consider how things taste if you really want your patient to follow nutrition guidelines.

Every single human is born with two copies of a taste gene called TAS2R38.However, some people inherit two versions of the gene called AVI,while others inherit just one copy of AVI and another variation of the gene called PAV.People with two AVI genes arent particularly sensitive to bitter tastes from certain compounds, but those with one PAV variant experience mild bitter sensations from certain foods.

Then, there is another group of people who inherit two PAV variant genes. This group, often referred to as super tasters, find certain foods extremely bitter.

Were talking a ruin-your-day level of bitter when they tasted the test compound. These people are likely to find broccoli, brussels sprouts and cabbage unpleasantly bitter; and they may also react negatively to dark chocolate, coffee and sometimes beer, Smith explains.

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It is estimated that roughly 50% of humans inherit both a PAV and AVI gene variant, while 25% are born with two PAV variants, and another 25% inherit two AVI variants.

Researchers went through food-questionnaire responses from 175 participants, and found that people with two copies of the PAV form of the gene (super tasters) were over two and a half times more likely to be in the bottom half of participants regarding number of vegetables consumed. The average age of the participant group was 52, and over 70% were females.

Interestingly, bitter sensitivity did not seem to influence the amount of salt, sugar, or fat that participants were eating.

We thought they might take in more sugar and salt as flavor enhancers to offset the bitter taste of other foods, but that wasnt the case. Down the road we hope we can use genetic information to figure out which vegetables people may be better able to accept and to find out which spices appeal to super tasters so we can make it easier for them to eat more vegetables, Smith concludes.

The study is set to be presented at the American Heart Associations Scientific Sessions 2019.

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Hate The Taste Of Vegetables? Your Genes May Be To Blame, Study Finds - Study Finds

Getting an earful from mum everyday for not eating green vegetables is a routine. Because most of us dont like eating vegetables and we keep thinking of excuses to escape the wrath of moms over veggies, of course.

As per the experts from the University of Kentucky School of Medicine, every person inherits two copies of a taste gene called TAS2R38 which encodes a protein that allows us to taste bitterness. Those who inherit two copies of a variant of this gene called AVI are not sensitive to bitter tastes while those who inherit one copy of AVI and another called PAV perceive bitter tastes.

So that [bitter] vegetable is disliked, and because people generalize, soon all vegetables are disliked, Duffy said. If you ask people, Do you like vegetables? They dont usually say, Oh yeah, I dont like this, but I like these others. People tend to either like vegetables or not, she added.

So, the next time your mother scolds you for not eating greenvegetables, you could always blame it on genes or on your forefathers! * wink *

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Hate Karela, Palak & Tinda? Your Genes May Be The Reason, Says Study - Storypick

The current study was initiated when a patient presented with a small brain size at birth and severe abnormalities in brain structures at the Baylor Hopkins Center for Mendelian Genomics (CMG), a center directed by Dr. Jim Lupski, professor of pediatrics, molecular and human genetics at Baylor College of Medicine and attending physician at Texas Childrens Hospital, said Dr. Hugo J. Bellen, professor at Baylor, investigator at the Howard Hughes Medical Institute and Jan and Dan Duncan Neurological Research Institute at Texas Childrens Hospital.

This patient and others in a cohort at CMG had not been infected by Zika virus in utero. They had a genetic defect that caused microcephaly. CMG scientists determined that the ANKLE2 gene was associated with the condition. Interestingly, a few years back the Bellen lab had discovered in the fruit fly model that ANKLE2 gene was associated with neurodevelopmental disorders. Knowing that Zika virus infection in utero can cause microcephaly in newborns, the team explored the possibility that Zika virus was mediating its effects in the brain via ANKLE2.

In a subsequent fruit fly study, the researchers demonstrated that overexpression of Zika protein NS4A causes microcephaly in the flies by inhibiting the function of ANKLE2, a cell cycle regulator that acts by suppressing the activity of VRK1 protein.

Since very little is known about the role of ANKLE2 or VRK1 in brain development, Bellen and his colleagues applied a multidisciplinary approach to tease apart the exact mechanism underlying ANKLE2-associated microcephaly.

The team found that fruit fly larvae with mutations in ANKLE2 gene had small brains with dramatically fewer neuroblasts brain cell precursors and could not survive into adulthood. Experimental expression of the normal human version of ANKLE2 gene in mutant larvae restored all the defects, establishing the loss of Ankle2 function as the underlying cause.

To understand why ANKLE2 mutants have fewer neuroblasts and significantly smaller brains, we probed deeper into asymmetric cell divisions, a fundamental process that produces and maintains neuroblasts, also called neural stem cells, in the developing brains of flies and humans, said first author Dr. Nichole Link, postdoctoral associate in the Bellen lab.

Asymmetric cell division is an exquisitely regulated process by which neuroblasts produce two different cell types. One is a copy of the neuroblast and the other is a cell programmed to become a different type of cell, such as a neuron or glia.

Proper asymmetric distribution and division of these cells is crucial to normal brain development, as they need to generate a correct number of neurons, produce diverse neuronal lineages and replenish the pool of neuroblasts for further rounds of division.

When flies had reduced levels of Ankle2, key proteins, such as Par complex proteins and Miranda, were misplaced in the neuroblasts of Ankle2 larvae. Moreover, live imaging analysis of these neuroblasts showed many obvious signs of defective or incomplete cell divisions. These observations indicated that Ankle2 is a critical regulator of asymmetric cell divisions, said Link.

Further analyses revealed more details about how Ankle2 regulates asymmetric neuroblast division. They found that Ankle2 protein interacts with VRK1 kinases, and that Ankle2 mutants alter this interaction in ways that disrupt asymmetric cell division.

Linking our findings to Zika virusassociated microcephaly, we found that expressing Zika virus protein NS4A in flies caused microcephaly by hijacking the Ankle2/VRK1 regulation of asymmetric neuroblast divisions. This offers an explanation to why the severe microcephaly observed in patients with defects in the ANKLE2 and VRK1 genes is strikingly similar to that of infants with in utero Zika virus infection, Link said.

For decades, researchers have been unsuccessful in finding experimental evidence between defects in asymmetric cell divisions and microcephaly in vertebrate models. The current work makes a giant leap in that direction and provides strong evidence that links a single evolutionarily conserved Ankle2/VRK1 pathway as a regulator of asymmetric division of neuroblasts and microcephaly, Bellen said. Moreover, it shows that irrespective of the nature of the initial triggering event, whether it is a Zika virus infection or congenital mutations, the microcephaly converges on the disruption of Ankle2 and VRK1, making them promising drug targets.

Another important takeaway from this work is that studying a rare disorder (which refers to those resulting from rare disease-causing variations in ANKLE2 or VRK1 genes) originally observed in a single patient can lead to valuable mechanistic insights and open up exciting therapeutic possibilities to solve common human genetic disorders and viral infections.

Others who contributed in this study are Hyunglok Chung, Angad Jolly, Marjorie Withers, Burak Tepe, Benjamin R. Arenkiel, Priya S. Shah, Nevan J. Krogan, Hatip Aydin, Bilgen B. Geckinli, Tulay Tos, Sedat Isikay, Beyhan Tuysuz, Ganesh H. Mochida, Ajay X. Thomas, Robin D. Clark and Ghayda M. Mirzaa. They are affiliated to one or more of the institutions: Baylor College of Medicine, Texas Childrens Hospital and the Jan and Dan Duncan Neurological Research Institute in Houston, TX; University of California at Davis and San Francisco; Zeynep Kamil Maternity and Children's Training and Research Hospital, Istanbul, Turkey; Marmara University School of Medicine, Istanbul, Turkey; Dr. Sami Ulus Research and Training Hospital of Women's and Children's Health and Diseases, Ankara, Turkey; Boston Childrens Hospital; Harvard Medical School, Boston, MA; Massachusetts General Hospital, Boston, MA; Loma Linda University Medical Center, Loma Linda, CA; University of Washington, Seattle, WA; and Seattle Children's Research Institute, Seattle, WA.

The study was funded by the National Institutes of Healths F32NS092270, NIH/NINDS R35NS105078, NIH U54NS093793, NIH R24OD022005, NIH/NINDS K08NS092898, Howard Hughes Medical Institute (HHMI), Medical Research Fellowship, Jordans Guardian Angels, a jointly funded NHGRI and NHLBI grant to the Baylor-Hopkins Center for Mendelian Genomics (UM1 HG006542) and the Huffington Foundation.

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How maternal Zika infection results in newborn microcephaly - Baylor College of Medicine News

The international group of scientists knew they were setting out to investigate an explosive subject: the hereditary basis of human same-sex behavior. Even so, the members of the prestigious Broad Institute in Cambridge, Massachusetts, may not have anticipated the magnitude of the public furor that erupted when they published their study, which identified several markers in certain genetic loci in the human genome related to same-sex sexual experience. The storm of reactions ranged from those who welcomed something seen as heralding significant progress in the field, to others who maintained that it would have been better if the scientists hadnt published anything.

The research results were published in full in the journal Science, at the end of August. This was the most extensive study of its kind ever conducted (there were about a half a million subjects), in which use was made of the GWAS (genome-wide association studies) method to analyze genetic big data. The researchers discovered five genetic markers (frequent, minor changes in the DNA segments of certain chromosomes) that appeared repeatedly among individuals who reported having had same-sex sexual experiences. Slight and frequent genetic variations were identified in both women and men, two others in men only and one more only in women.

No less important in the study, entitled Large-scale GWAS reveals insights into the genetic architecture of same-sex sexual behavior, is the scientists claim that a large number of genetic markers, perhaps even thousands, might operate simultaneously together although each in and of itself is of minuscule weight and influence ones same-sex orientation. Moreover, their study led the researchers to the conclusion that human genetics can explain up to 32 percent of same-sex sexual behavior.

What is at issue here, however, is not what the study contains but what it does not contain. As Melinda Mills, a sociology professor at Oxford, writes in the same issue of Science, there is no way that the researchers findings can be used as a tool to accurately predict same-sex behavior. Specifically, the fact that genetics can explain up to 32 percent of the fact that someone is gay or lesbian, does not mean that sexual identity is determined primarily by environmental factors not to mention social ones. This story is far more complex and has not yet been fully deciphered. Mills views are shared by Andrea Ganna, one of the chief authors of the new study.

What we basically do is statistical associations between having and not having these genetic markers and having or not having same-sex behavior, Ganna told Haaretz in a phone interview. Because we had this uniquely large study, he continued, which allowed us to have robust conclusions, and because we had the technology to measure the genetic markers of so many individuals, the time was right to confirm something that we expected: There is no one specific gay gene. Instead there are a lot of relatively common genetic markers, genetic mutations, that have a small effect on same-sex behavior.

At the same time, adds Ganna, a geneticist at Harvard Medical School and at Finlands Institute of Molecular Medicine, Not everyone is interpreting the fact that theres no single gay gene in the right way.

Gannas concern is shared by scientists around the world. Theyre worried that the researchers findings will fuel prejudice and discrimination against the LGBTQ community, and even spark calls for genetic engineering and genetic diagnosis among its members. So serious are these apprehensions that some have wondered whether the study would not do more harm than good.

As a queer person and a geneticist, I struggle to understand the motivations behind a genome-wide association study for non-heterosexual behavior, Joseph Vitti, a postdoctoral researcher at the Broad Institute, wrote on its blog, adding, I have yet to see a compelling argument that the potential benefits of this study outweigh its potential harms [T]he results presented not only oversimplify the question of biological causality, but also threaten direct damage by perpetuating the stereotype of LGBTQIA+ people as imprudent, while also likening same-sex attraction to a medical or psychological disorder.

Moreover, a website called The American Conservative posted an article entitled Not Born This Way After All? which wondered, skeptically: If the study proves that homosexuality is related to the environment, above all, and not to heredity why isnt it right and proper, in scientific terms, to allow those who so desire to undergo treatment in order to reduce their same-sex desires, which have now been shown not to be genetic?

That, however, is a simplistic reading of the studys findings. According to Michael Bailey, a professor of psychology at Northwestern University in Illinois, who was not involved in the study but has been conducting research on sexual orientation for 30 years, Its very important to understand that environment does not simply refer to social surroundings, like what your parents teach you and what kids you know, trauma and so on theres also a biological environment that begins right after conception.

Three years ago, Bailey and several colleagues published a survey of all the studies and professional literature in the field. The best studies have shown that genes are probably important but not overwhelmingly important, he tells Haaretz. We estimated in our 2016 review that 30 percent of the variation in sexual orientation is due to genetic variations. It may be this finding that led him to conclude that it is the biological environment that is mostly important. Bailey is convinced that men are born with their sexual orientation and that it is not subsequently acquired at any stage. He notes that there are several cases, I think there are seven throughout the professional literature, in which a baby boy was changed into a girl for medical reasons and was raised as a girl. When you follow these individuals through adulthood, you find that they are attracted to women and not to men.

In Baileys view, the best example of how biological-environmental factors can influence sexual orientation is the fraternal birth order effect. The phenomenon, whose existence is well established, he says, shows that the more older brothers a man has, the more likely he is to be homosexual. In practice, every older biological brother increases the probability that the youngest brother will be gay by about 33 percent. Thus, if the probability that a man with no older brothers will be gay is 2 percent, one older brother will increase the probability to 2.6 percent, and a second, third and fourth brother to 3.5 percent, 4.6 percent and 6 percent, respectively. Whats not yet clear is the reason for this.

In my mind, Bailey suggests, the best hypothesis as to why this happens is that a mothers immune system becomes increasingly active and produces antibodies against male proteins over successive births.

Fingers and hands

Behind this hypothesis is one of the most influential figures in the field, American-Canadian clinical psychologist and sexologist Ray Milton Blanchard. He was also among those who linked the fraternal birth order effect to another phenomenon of interest to scientists: the connection between being left-handed and having a same-sex orientation. The most extensive study in this regard was conducted in 2000, incorporating 20 different studies involving 7,000 gay male and female subjects and 16,000 heterosexual ones. It was found that gay men were 34 percent more likely to be left-handed. The situation was more extreme among lesbians: They were seen to have a 91 percent greater chance than straight women of writing with their left hand.

As a result, six years later, a research team led by Blanchard argued that the fraternal birth-order effect is relevant only among right-handed men. The reason is that, in any case, left-handed men who dont have older brothers already have a greater likelihood of being gay than right-handed men with such siblings.

A persons dominant hand turns out to be significant in another sense as well. An article published two years ago (about a study in which all the subjects had taken part in a gay pride parade in Toronto) found a connection between that hand and the gay persons role in bed: that is, the proportion of left-handed gays who defined their sexual behavior as passive or versatile (i.e., sometimes passive, sometimes not) was significantly higher than among those who described themselves as actives who clearly tended to be right-handed.

In research conducted over the years on the subject of the connection between sexual orientation and other attributes of the body, the hand holds a place of honor. But while Blanchard developed his theory on the basis of the whole hand, sometimes a few fingers are also enough: two, to be exact. In his 1998 study, British biologist John Manning confirmed a relatively old hypothesis, first put forward in Germany almost 150 years ago. Its gist is that the proportion between the length of index and ring fingers is, typically, different in men and women. Manning found that this phenomenon was detectable as early as age 2, which led to the observation that its source lies in the differences in testosterone and estrogen levels that already exist in the womb hereinafter: a biological-environmental factor.

Manning did not emphasize the element of sexual orientation in the two books and over 60 articles he wrote on this subject, but in the two decades that have elapsed since his study, more than 1,400 papers have been written on the ratio between the length of the second and fourth fingers (known as 2D:4D) and the connection between it and the level of risk of contracting certain diseases, as well as personality traits, cognitive and athletic abilities and sexual orientation.

One such study, published in 2010, maintained that straight and lesbian women are differentiated by the ratio between the length of the index and ring fingers, with lesbians tending to show a more masculine ratio i.e., closer to the average difference between the length of the fingers, among men. However, no such differences were found between gay and straight men.

Last year a team of scientists led by a British psychologist measured the fingers of 18 pairs of identical female twins, one lesbian, the other straight. Overall, differences in proportion were documented only in the lesbians and only in their left hand, and were comparable to the situation among men. This fact, the team concluded, could indicate a heightened exposure to testosterone in the womb but their study was based on a very small sample and drew much criticism. The critics charged that the conclusion was based on an overly simple means of measurement: of the way only two variables impacted each other. And, they added to bolster their argument, findings of studies involving those fingers have not been replicated in scientific experiments.

The field of gay science has been on a roll in recent years, but has a far longer history. Its modern phase dates to the early 1990s, when scientists began to publish increasing numbers of studies arguing that sexual orientation has a biological component. A leading scientist in this field is British-American neurobiologist Simon LeVay, who in 1990 performed autopsies on the bodies of 41 people: 19 gay men, 16 straight men and nine women. He discovered that the brain cells known as INAH-3 among the deceased gay men were relatively small, and closer in size to those of women than to heterosexual males.

In 1991, LeVay told Haaretz in a phone conversation, I published a study that got a lot of media attention, related to my observation that there was a region inside the hypothalamus that was different in size between men and women, and also between gay and straight men My additional finding was the difference in size between gay and straight men in this region inside the hypothalamus that is involved in the regulation of sexual behavior.

Adds LeVay, My general feeling is that there are certainly strong biological influences on peoples sexual orientation, but we cant say everything is genetic.

In the spirit of the period, and in light of the AIDS epidemic at the time, LeVay tried to be as cautious as possible about his conclusions. Its important to stress what I didnt find, he said in an interview to Discover magazine, in 1994. I did not prove that homosexuality is genetic, or find a genetic cause for being gay. I didnt show that gay men are born that way, [which is] the most common mistake people make in interpreting my work.

Three decades after publishing his study, he still thinks media coverage is doing an injustice to research even if its not his. Ive seen some headlines saying, basically, that this study [i.e., that of Ganna and his associates] shows its not genetic, or that are no gay genes, or something like that; and, of course, its not what the study shows at all.

Truly gay

In recent decades, scientific research (on men and women alike) in this realm has relied on an additional field: molecular genetics. The pioneer is geneticist Dean Hamer, who in 1993 conducted the first study of its kind.

We noticed that being gay, for males, tended to pass down through the mothers side of the family, he told Haaretz. And that is characteristic in genetics of something on the X chromosome because males get their X chromosomes from their moms That led us to look in families where there were gay brothers, to see if they shared anything on the X chromosome.

And thus, recalls Hamer, he and his team discovered Xq28: a genetic marker that plays a part in determining whether a person will be heterosexual or gay. He emphasizes that this is a factor, its not the factor and actually, overall, its not even the most important factor. He adds, Whats good about genetic studies, is that you know that whatever you find is a causal factor, because of course people are born with their genes, and its not something that changes over time.

LeVay, he explains, is looking directly at the brain, and were looking at what we think is building the brain and genes. Yet, its very difficult to know whether one was born with a brain like that, or whether that brain developed that way because of your behavior the causality is rather unknown.

At the same time, Hamer adds, That doesnt mean there arent specific pathways, because there has to be some sort of a pathway in the brain that controls sexual orientation. We know, for example, that the reason you become a male or a female is very simple: If you have a certain gene on the Y chromosome, you will produce male hormones, and if you have those you make a penis and scrotum and you become male. Accordingly, Theres probably some pathway in the brain that does same thing for sexual orientation, but were not going to discover it from genetics The answer will probably emerge from some sort of very sophisticated brain and developmental studies.

For 35 years, Hamer accumulated experience as a scientist at the National Institutes of Health in Bethesda, Maryland. That period is behind him. He doffed the white coat and now lives in Hawaii, where he makes films. But even if hes no longer occupied with research, it still occupies him.

Hamer: Back in the 1990s, I, along with all the scientists involved, believed that if we did good genetic studies wed find the important genes. For example, well find a gene that is responsible for the production of testosterone, and if its functioning was low, it would be possible to say that this is the cause of homosexuality in a particular person. But it turns out that it doesnt work that way. For every mental trait that has been studied everything you can imagine in the brain, for every single trait, theres a [vast number of] genes not to mention a host of complex societal and environmental factors.

For his part, Hamer has much praise for the Broad Institute study: The new GWAS study is really important, because for the very first time they used a huge sample and they mapped every inch of the genome. And this has never been done before. All the other studies were much smaller, or used many fewer genetic markers. But he also demurs: Whats very important is to look at what they actually analyzed. They didnt analyze people who were gay or lesbian, but anyone who had one single same-sex experience, which is quite different... They were measuring something more like openness to sexual experimentation.

As Hamer sees it, If you look for those five markers, or even just the three strongest markers, they are not necessarily found in people who actually identify as gay or lesbian. If you take people who are gay, like me, and look for those markers theyre not significantly there.

Hamer thinks that the whole field is lagging behind because of insufficient research, owing to the stigmas that plague the subject. I dont think sexuality is any more complicated than many other areas of human personality and individual differences, he observes, noting, We formally established that male sexuality is something that is deeply ingrained in people, its not any sort of choice really. It starts really early in life, and it has a major biological component to it. But, how it works? What the biological component is? Were completely unaware and dont know anything, and we barely know more than we did 25 years ago, or in the 1940s, when Kinsey did his work, to be honest.

Hamer was referring to biologist Alfred Kinsey, who in 1948 stunned the American public with his book, Sexual Behavior in the Human Male, which addressed previously taboo subjects, and challenged the traditional beliefs and existing knowledge about human sexuality. Kinsey had conducted a survey of men, which found that 37 percent of his subjects said they had undergone a homosexual experience of some kind, and 10 percent said they had been exclusively gay for three years of their adult life a statistic which to this day is generally said to represent the proportion of people engaging in same-sex behavior.

At the same time, subsequent studies reveal that the percentage of people who define themselves as exclusively homosexual is far lower, though it fluctuates from one article to the next. For example, a 2011 survey of nine different studies on the subject revealed that approximately 3.5 percent of Americans identify themselves as gays, lesbians or bisexuals. A poll involving 1,000 Jewish Israelis in 2012 found that 11.3 percent of the male respondents and 15.2 percent of the female ones said they felt an attraction to members of the same sex. However, only 8.2 percent of the men categorized themselves as gay or bisexual, while 4.8 percent of the women said they were lesbian or bisexual.

For his part, Ganna, of the Broad Institute, understands some of the criticism of his research. What we studied is not related directly to the biology, but to extended environmental factors related to it. Its not about our sample size once you have a lot of individuals, you can capture very small effects. But are these directly influencing same-sex behavior, or other things related to this topic? As a medical example, think about a study that looks for associations between genetic markers and lung cancer. In that example, what we found are genetic variants regarding how much you smoke, which is related to lung cancer.

One of the lessons, and one of the most interesting points arising from the study has to do, says Ganna, with the mode of measurement that had been in use since 1948, when Kinseys scale ranked individuals as being between 0 (totally heterosexual) and 6 (totally homosexual).

Ganna: Basically, the tendency is to locate individuals on a continuum. You can supposedly be anywhere between 100 percent heterosexual to 100 percent homosexual, which implies that the more youre homosexual, the less youre heterosexual, and vice versa. We show that this assumption actually doesnt hold water: When we look at the genetic data, its not that straightforward, theres no simple continuum of sexuality.

So, actually, you are refuting the Kinsey scale?

Ganna: Thats exactly one of our conclusions. What were now doing is, rather than asking people to put themselves on a scale somewhere between being exclusively heterosexual or exclusively homosexual, we ask them how much theyre attracted to men and women. You could be attracted to either of them, very attracted to both of them or to one more than the other. And that information will be crossmatched with genetic markers.

In the final analysis, he adds, We showed that this is just another natural human variation. Sexual orientation, similar to many other behavioral traits, is complicated and is composed of different factors. The interesting thing is how genetics and environment work together. If you think about how much more prevalent same-sex behavior has become lately, people engage in it more than in the past. And thats clearly not because our genetics are changing. Its because of the environment, because society is becoming more open and laws are changing.

Further research should focus on the relationship between environmental factors and genetics, Ganna says, and on how they interact. Its somewhat misleading to think of nature and nurture as separate aspects; they both contribute. So, it would be wrong to say that you can use only DNA to predict if someone will engage in same-sex behavior, but you also cant say its simply a [matter of] choice.

In summary, he says, I think that the more people who will understand that there are genetic and environmental components to sexual behavior, the better and this is a message that goes beyond just sexuality.

Choice and lifestyle

However, the relationship between science and the environment, and particularly the people living in it, is a complicated one. The subject definitely should be studied, but the social aspect of it is problematic, says LeVay, the neurobiologist. I am gay myself, and I feel strongly that gay people should be valued and accepted into society, regardless of what caused their sexual orientation. I dont think its vital for gay liberation to prove that gay people cant help but be gay there are plenty of other reasons [for accepting them], including basic human rights.

At the same time, he adds, this issue is socially relevant, because of traditional notions that see same-sex relations as a choice, a lifestyle or sinful behavior.

In recent years, there have been many studies showing that peoples attitudes toward homosexuality are closely tied to their beliefs about what makes people gay, says LeVay, citing a survey that showed there was a high probability that people who think homosexuality is a choice will object to a gay person being their childrens teacher which in a way might make sense, he adds: If you think being gay is something infectious, socially contagious, and you didnt want your kid to be gay, then you wouldnt want their teacher to be gay ... It follows that demonstrating that biological factors are involved, helps counter those ideas. Still, Im a bit ambivalent about the use of this type of research as some sort of a political weapon in the struggle for gay rights.

The Broad Institute study contains a reminder of the problems and stigmas that still exist with regard to the LGBTQ community. One of the parameters it considers are genetic correlations between genes that are ascribed to homosexuality, and certain psychological problems.

Bailey, the psychologist: One thing that was perceived as controversial, was to look for and find a genetic overlap between homosexual sex genes and genes associated with depression. Its not the same as saying all people who engage in homosexual sex are depressed for genetic reasons, but its also not something that can be easily ignored. There are assumptions that the higher rates of depression among gay men and lesbians is due to the way they are mistreated by society, but the evidence for that is not so overwhelming. There is also the fact, for example, that you have as high a rate of depression among homosexual men in the Netherlands, which is very tolerant, as you have in some less tolerant places, like the United States.

Ganna, for his part, tries to soften that criticism: Even if we see genetic overlap, or correlation, it is not set in stone that weve found a biological mechanism that causes depression and same-sex behavior, he says. There are many explanations for why this one genetic marker is associated with both things. But finding these correlations help us study human traits in general.

In the meantime, there is a price to be paid for conducting research in this realm, which all those involved must be aware of. Reminders of this abound, and are almost routine. In some cases whats at stake is not even a groundbreaking study or one of tremendous scientific importance. In 2017, for example, two researchers from Stanford published an article stating that gay men are predicted to have smaller jaws and chins, slimmer eyebrows, longer noses, and larger foreheads; the opposite should be true for lesbians. In the next stage, they created a facial-recognition program with the aid of more than 14,000 images taken from a singles site of straights and LGBTQs. The program was able to distinguish between gays and lesbians and heterosexuals with an accuracy of 81 percent for men and 71 percent for women, in contrast to an average rate of successful human guesses of 61 percent and 54 percent, respectively. Even though the program achieved relatively impressive results, the study as such drew widespread criticism not unusual for researchers engaged in such studies.

The Stanford gays identification program may be an extreme example, in this respect, but its also a byproduct of the considerable surge in studies in this field, a trend that began in the early 1990s. Together with the scientific community, media interest in the subject of same-sex orientation and its causes has contributed substantially to transmitting messages and shaping public opinion.

In the United States, this can be seen in a series of polls conducted by Gallup, Inc. The first one, conducted in 1977, found that only 13 percent of the respondents believed that homosexuality is an innate tendency, while 56 percent attributed it to environmental factors. This approach remained largely constant until the period between 1989 and 1996, when the rate of those supporting the innate thesis leaped from 19 percent to 31 percent; by 2001, it stood at 40 percent. Almost a decade and a half later, the annual poll produced, for the first time, a larger proportion who agreed with the innate argument. The latest survey, from the end of last year, showed this trend continuing: More than half of the American public believes that gay people are born with their sexual orientation, whereas only 30 percent attribute it to environmental factors (10 percent said both factors play a part, 4 percent cited other factors and 6 percent said they werent sure).

Changes in the perceptions of the origins of sexual orientation are having a pronounced effect on the struggle LGBTQ individuals are waging for equal rights. The latest Gallup poll shows that an absolutely majority (88 percent) of those who believe that homosexuality is an innate trait also support legitimizing same-sex marriages. In contrast, most of those who see this orientation as being environmentally driven (61 percent) are against.

When it comes to public opinion, which is very important, the born this way idea has been really resonant and has had a very positive impact on society, Hamer maintains. Public opinion polls asked people whether they think [gays] were born this way or not, and we know that believing that homosexuality is innate correlates with having positive feelings toward gay rights. Overall, its been important in educating the public about who we are, as gay people.

Such messages are reaching Israel as well. A poll conducted by the Dialog Institute for Haaretz at the end of 2013 found that 70 percent of those questioned favored full rights for same-sex couples, while 64 percent specifically backed their right to surrogacy. However, two polls conducted in the wake of the surrogacy law protest in July 2018 presented slightly lower numbers: About 57 percent of respondents expressed support for the right of same-sex male couples to surrogacy.

These polls did not ask Israelis whether they believe the origin of same-sex orientation is innate or environmental. If you ask Bailey, though, that doesnt really matter.

Ive gone to great lengths to try to persuade people not to base equal rights for gay people on the causal hypothesis, he says. Its a terrible idea to say gay people should have equal rights because they were born that way. Its terrible in part because some criminals might be born that way, and you dont want to them to have the same rights. Being gay doesnt harm anybody, other than people who are close-minded and easily offended. Preventing people from expressing their homosexuality is quite destructive for them. Thats true whether gay people are born that way or not.

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Is sexual orientation genetic? Yes and no, an extensive study finds - Haaretz

Walter Suza, Iowa State University

(The Conversation is an independent and nonprofit source of news, analysis and commentary from academic experts.)

Walter Suza, Iowa State University

(THE CONVERSATION) Growing up in Tanzania, I knew that fruit trees were useful. Climbing a mango tree to pick a fruit was a common thing to do when I was hungry, even though at times there were unintended consequences. My failure to resist consuming unripened fruit, for example, caused my stomach to hurt. With such incidents becoming frequent, it was helpful to learn from my mother that consuming the leaves of a particular plant helped alleviate my stomach pain.

This lesson helped me appreciate the medicinal value of plants. However, I also witnessed my family and neighboring farmers clearing the land by slashing and burning unwanted trees and shrubs, seemingly unaware of their medicinal value, to create space for food crops.

But this lack of appreciation for the medicinal value of plants extends beyond my childhood community. As fires continue to burn in the Amazon and land is cleared for agriculture, most of the concerns have focused on the drop in global oxygen production if swaths of the forests disappear. But Im also worried about the loss of potential medicines that are plentiful in forests and have not yet been discovered. Plants and humans also share many genes, so it may be possible to test various medicines in plants, providing a new strategy for drug testing.

As a plant physiologist, I am interested in plant biodiversity because of the potential to develop more resilient and nutritious crops. I am also interested in plant biodiversity because of its contribution to human health. About 80% of the world population relies on compounds derived from plants for medicinesto treat various ailments, such as malaria and cancer, and to suppress pain.

Future medicines may come from plants

One of the greatest challenges in fighting diseases is the emergence of drug resistance that renders treatment ineffective. Physicians have observed drug resistance in the fight against malaria, cancer, tuberculosis and fungal infections. It is likely that drug resistance will emerge with other diseases, forcing researchers to find new medicines.

Plants are a rich source of new and diverse compounds that may prove to have medicinal properties or serve as building blocks for new drugs. And, as tropical rainforests are the largest reservoir of diverse species of plants, preserving biodiversity in tropical forests is important to ensure the supply of medicines of the future.

Plants and new cholesterol-lowering medicines

The goal of my own research is to understand how plants control the production of biochemical compounds called sterols. Humans produce one sterol, called cholesterol, which has functions including formation of testosterone and progesterone - hormones essential for normal body function. By contrast, plants produce a diverse array of sterols, including sitosterol, stigmasterol, campesterol, and cholesterol. These sterols are used for plant growth and defense against stress but also serve as precursors to medicinal compounds such as those found in the Indian Ayurvedic medicinal plant, ashwagandha.

Humans produce cholesterol through a string of genes, and some of these genes produce proteins that are the target of medicines for treating high cholesterol. Plants also use this collection of genes to make their sterols. In fact, the sterol production systems in plants and humans are so similar that medicines used to treat high cholesterol in people also block sterol production in plant cells.

I am fascinated by the similarities between how humans and plants manufacture sterols, because identifying new medicines that block sterol production in plants might lead to medicines to treat high cholesterol in humans.

New medicines for chronic and pandemic diseases

An example of a gene with medical implications that is present in both plants and humans is NPC1, which controls the transport of cholesterol. However, the protein made by the NPC1 gene is also the doorway through which the Ebola virus infects cells. Since plants contain NPC1 genes, they represent potential systems for developing and testing new medicines to block Ebola.

This will involve identifying new chemical compounds that interfere with plant NPC1. This can be done by extracting chemical compounds from plants and testing whether they can effectively prevent the Ebola virus from infecting cells.

There are many conditions that might benefit from plant research, including high cholesterol, cancer and even infectious diseases such as Ebola, all of which have significant global impact. To treat high cholesterol, medicines called statins are used. Statins may also help to fight cancer. However, not all patients tolerate statins, which means that alternative therapies must be developed.

Tropical rainforests are medicine reservoirs

The need for new medicines to combat heart disease and cancer is dire. A rich and diverse source of chemicals can be found in natural plant products. With knowledge of genes and enzymes that make medicinal compounds in native plant species, scientists can apply genetic engineering approaches to increase their production in a sustainable manner.

Tropical rainforests house vast biodiversity of plants, but this diversity faces significant threat from human activity.

To help students in my genetics and biotechnology class appreciate the value of plants in medical research, I refer to findings from my research on plant sterols. My goal is to help them recognize that many cellular processes are similar between plants and humans. My hope is that, by learning that plants and animals share similar genes and metabolic pathways with health implications, my students will value plants as a source of medicines and become advocates for preservation of plant biodiversity.

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This article is republished from The Conversation under a Creative Commons license. Read the original article here: http://theconversation.com/dwindling-tropical-rainforests-mean-lost-medicines-yet-to-be-discovered-in-their-plants-126578.

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Dwindling tropical rainforests mean lost medicines yet to be discovered in their plants - Thehour.com

On 19 November, the UK BioBeat19 summit goes to Stevenage to discuss the potential of cell and gene therapy and how to accelerate these transformational medicines.

Victoria Higgins of GSK and Miranda Weston-Smith from BioBeat spoke to two panellists who gave a sneak peek of their remarks and agree wholeheartedly that the discovery side and clinical side work best when they are teamed up.

Sophie Papa, an oncologist at Guys Cancer at Guys and St Thomas NHS Trust, and Aisha Hasan, a clinical development lead at GSK, both recognise the big challenge ahead for cell therapy researchers: to dial up efficacy and dial down toxicity.

Cell and gene therapies, with their remarkable potential to transform medicine, have seen some important but hard-won milestones: it took 20 years of combined academic and industry research to deliver the first gene therapy approval in 2016 and today there are two CAR-Ts approved for haematological malignancies.

Whilst CAR-Ts recognise proteins expressed on the tumour cell surface, making them ideal for targeting blood cancers, more complicated but with greater potential to address solid tumours are the gene modified TCR-T technologies.

These harness the power of T cells to specifically target and destroy tumours even on the inside of cells. TCR-Ts come with an additional level of complexity, but potentially open the door to a range of untreatable cancer types.

Looking at the TCR opportunity is where Sophie Papa sees the inherent trade-off between risk and benefit as an academic clinician whos now evaluating modified T-cell based therapies in clinical trials.

Sophie urges her peers to take courage. It is important to be brave and tolerant of certain toxicities. Academic clinicians and drug researchers need to work closely together to engage the regulators in early discussion, so that we can move cell therapies earlier in treatment schedules as soon as feasible.

Timing is critical to enable patients to be treated when they are physically fit so they can better tolerate these complex and potentially toxic treatments.

From her perspective, this is not an either/or, but an area where discussion and open dialogue will allow us to make the most of the opportunity. By allowing clinical academics to play a lead role in developing guidelines to manage patient safety, we can address legitimate concerns but not let them stand in the way of clinical development, she says.

Aisha brings the perspective of drug discovery and development and starts by asking what is in the realm of the possible from a design perspective.

She says: A superior T-cell therapy will require engineering approaches that enhance efficacy on one-end while also incorporating switches to minimise toxicity.

For example, in a counter-intuitive way, a T-cell with high-killing capacity actually can create dangerous levels of inflammation in the body, due to the rapid death of cancer cells. But the beauty of drug design opens up options:By building a switch within the engineered T-cells, researchers can inactivate the T-cells and prevent harm to the patient, says Aisha.

But this creative problem solving requires open dialogue between clinicians and pharma. Aisha says: The more we talk about clinical need and toxicity benchmarks, the more sophisticated we can be when developing the next generation of enhanced engineered cell therapies.

Theres no doubt that the challenges of delivering cell and gene therapy span the full spectrum of issues related to medicine development. However, the potential for both curative therapy and commercial opportunity is tremendous.

The scientific, clinical, technical, regulatory and commercial challenges are all surmountable when everyone in the ecosystem work together towards a shared goal, united by an unwavering focus on the patient.

Sophie and Aisha are speaking about the translational journey from science to bedside at the BioBeat19 summit.

The BioBeat19 summit on Accelerating cell and gene therapy, 1-6pm, Tuesday 19 November, GSK Stevenage. Guarantee your place by registering at http://www.biobeat19.org

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Next generation cell and gene therapies: fine tuning the promise - Business Weekly