Dear Dr. Roach: I read your recent column regarding identical twins where one of the two was balding while his twin was not. Within my extended family, there are identical twin brothers, who also were almost impossible for family members to differentiate.
Nature News were among the first to break the story based on a conference abstract. Others quickly followed suitmany using a press release issued by the conference organizers. Meanwhile, the mood at the conference has been decidedly less complimentarywith several geneticists criticizing the methods presented in the talk, the validity of the results, and the coverage in the press.
The relationship between biology and sexual orientation is a subject of research. While scientists do not know the exact cause of sexual orientationthey theorize that a combination of genetic, hormonal, and social factors determines it. Biological theories for explaining the causes of sexual orientation are favored by scientists  and involve a complex interplay of genetic factors, the early uterine environment and brain structure.
A pride march in Belgrade last month. Indeed, over the past 2 decades, researchers have turned up considerable evidence that homosexuality isn't a lifestyle choice, but is rooted in a person's biology and at least in part determined by genetics. A new study of male twins, scheduled for presentation at the annual meeting of the American Society of Human Genetics ASHG in Baltimore, Maryland, today, could help explain that paradox.
Identical twins are exactly alike—or are they? After all, they're always the same sex, they look exactly alike, they often dress the same or at least their mothers dress them the same when they're littleand they tend to share certain mannerisms and other features. A frequently asked question about identical twins is, "Do they have the same DNA?
The second study in several months to strongly suggest a genetic component to homosexuality has been reported by researchers at Northwestern University and Boston University. The study found that more than half of the 56 identical twins of homosexual males studied were also gay, researchers report today in the Archives of General Psychiatry. This provides new evidence that genetics play a more important role than environment in the development of homosexuality, said psychologist J.
Reuters - U. Findings from the study, which has yet to be published or reviewed in detail by other scientists, were presented at a meeting of the American Society of Human Genetics in Baltimore. It followed 37 pairs of identical male twins in which one was homosexual and one heterosexual, and 10 sets of twins in which both males were homosexual.
To preserve these articles as they originally appeared, The Times does not alter, edit or update them. Occasionally the digitization process introduces transcription errors or other problems. A new study of twins provides the strongest evidence yet that homosexuality has a genetic basis, researchers say, though they say other factors like social conditioning may be important.