"We previously had no good understanding of why the sexes vary in their relationship to different diseases," explained Xia Yang, Ph.D., first author and postdoctoral fellow in cardiology at the David Geffen School of Medicine at UCLA. "Our study discovered a genetic disparity that may explain why males and females diverge in terms of disease risk, rate and severity."
"This research holds important implications for understanding disorders such as diabetes, heart disease and obesity, and identifies targets for the development of gender-specific therapies," said Jake Lusis, Ph.D., co-investigator and UCLA professor of human genetics.
The UCLA team examined brain, liver, fat and muscle tissue from mice with the goal of finding genetic clues related to mental illnesses, diabetes, obesity and atherosclerosis. Humans and mice share 99 percent of their genes.
The scientists focused on gene expression -- the process by which a gene's DNA sequence is converted into cellular proteins. With the help of Rosetta Informatics, the team scrutinized more than 23,000 genes to measure their expression level in male and female tissue.
What they found surprised them. While each gene functioned the same in both sexes, the scientists found a direct correlation between gender and the amount of gene expressed.
"We saw striking and measurable differences in more than half of the genes' expression patterns between males and females," said Dr. Thomas Drake, co-investigator and UCLA professor of pathology. "We didn't expect that. No one has previously demonstrated this genetic gender gap at su
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Source:University of California - Los Angeles