By comparing the testosterone levels of five-month old pairs of twins, both identical and non-identical, University of Montreal researchers were able to establish that testosterone levels in infancy are not inherited genetically but rather determined by environmental factors. “Testosterone is a key hormone for the development of male reproductive organs, and it is also associated with behavioural traits, such as sexual behaviour and aggression,” said lead author Dr. Richard E. Tremblay of the university’s Research Unit on Children’s Psychosocial Maladjustment. “Our study is the largest to be undertaken with newborns, and our results contrast with the findings gained by scientists working with adolescents and adults, indicating that testosterone levels are inherited.” The findings were presented in an article published in Psychoneuroendocrinology on May 7, 2012. (more…)
Tag Archives: testosterone
It is well documented that male birds seduce females using their songs, colourful plumage and courtship dances. These signals reflect male genetic quality and will be graded by the female to determine a male’s potential as a mate. The stronger the grade, the better the odds of being selected.
But this basic rule isn’t the only yardstick used by females. As surprising as it seems, birds know how to use data from their social environment to maximize their chances of reproduction. Frédérique Dubois, a professor at the Université de Montréal Department of Biological Sciences, has already demonstrated that female Zebra Finches will favour a male chosen by another female. Dubois refers to this as imitation and the use of “public information” in choosing a mate. (more…)
*Researchers discover molecular mechanism behind drink’s prophylactic effect*
Coffee, that morning elixir, may give us an early jump-start to the day, but numerous studies have shown that it also may be protective against type 2 diabetes. Yet no one has really understood why.
Now, researchers at UCLA have discovered a possible molecular mechanism behind coffee’s protective effect. A protein called sex hormone–binding globulin (SHBG) regulates the biological activity of the body’s sex hormones, testosterone and estrogen, which have long been thought to play a role in the development of type 2 diabetes. And coffee consumption, it turns out, increases plasma levels of SHBG. (more…)
When their romantic partners are not quintessentially masculine, women in their fertile phase are more likely to fantasize about masculine-looking men than are women paired with George Clooney types.
But women with masculine-looking partners do not necessarily become more attracted to their partners, a recent study co-authored by a University of Colorado at Boulder researcher concludes. (more…)
Schizophrenia is a mental disorder that differs between the sexes in terms of age at onset, symptomatology, response to medication, and structural brain abnormalities. Now, a new study from the Université de Montréal shows that there is gender difference between men and women’s mental ability – with women performing better than men. These findings, published recently in, Schizophrenia Research, have implications for the more than 300 000 affected Canadians.
“We are the first to report sex differences in brain function of schizophrenics,” says Université de Montréal professor, Adrianna Mendrek a researcher at the Centre de Recherche Fernand-Seguin, Hospital Louis-H Lafontaine. “We chose to study a task involving mental rotation of a three dimensional image because in healthy men and women, this consistently elicits differences in terms of reaction time and performance accuracy.” (more…)
*Researchers urge appropriate use of androgen deprivation therapy*
ANN ARBOR, Mich. — Men treated with hormone-based therapy for prostate cancer faced a 30 percent to 40 percent higher risk of colorectal cancer, compared to patients who did not receive this treatment, according to a new study.
The study looked at use of androgen deprivation therapy, a common type of treatment for prostate cancer that involves blocking the male hormone testosterone through either surgical removal of the testicles or a series of injections. It’s been shown to benefit men with advanced cancers, but its benefit for less-advanced disease is unclear. Still, more than half a million men in the United States currently receive this therapy. (more…)