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.
I n a recent Guardian articleSimon Copland argued that it is very unlikely people are born gay or presumably any other sexual orientation. Scientific evidence says otherwise. It points strongly to a biological origin for our sexualities.
Eight major studies of identical twins in Australia, the U. Neil Whitehead, PhD. Whitehead worked for the New Zealand government as a scientific researcher for 24 years, then spent four years working for the United Nations and International Atomic Energy Agency.
One object is to report the number of concordant and discordant, monozygotic MZ and dizygotic DZ pairs observed. A second object is to examine the frequency of homosexuality in twins per se. One of the twin pairs was from a family deserving special attention.
We use Scripture, experience and knowledge to guide us in faith and life. Some of our knowledge comes from science. Sadly, misunderstandings and misrepresentations of scientific research have been used to encourage people to ignore Scripture, abandon faith and embrace homosexuality as if they have no choice.
By Andy Coghlan. A genetic analysis of pairs of gay brothers, including sets of twins, has provided the strongest evidence yet that gay people are born gay. The study clearly links sexual orientation in men with two regions of the human genome that have been implicated before, one on the X chromosome and one on chromosome 8.
The reasons behind why people are gay, straight or bisexual have long been a source of public fascination. Indeed, research on the topic of sexual orientation offers a powerful window into understanding human sexuality. Among the indigenous Zapotec people in southern Mexico, individuals who are biologically male and sexually attracted to men are known as muxes.
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.
A new study suggests that a love of sailor caps and mesh thongs may be connected to a protein on the Y chromosome. The idea that sexuality is tied to biology is nothing new: Scientists have been looking for the "gay gene" for decades, and more recent research has demonstrated that boys with older brothers are more likely to grow up to be gay. Now, we may know why. Andy Coghlan from New Scientist explains:.