"Men are 1.5 times more likely to develop Parkinson's disease than women," said Dr. Eric Vilain, associate professor of human genetics at the David Geffen School of Medicine at UCLA. "Our findings may offer new clues to how the disorder affects men and women differently, and shed light on why men are more susceptible to the disease."
In 1990, British researchers identified SRY as the gene that determines gender and makes embryos male. Located on the male sex chromosome, SRY manufactures a protein that is secreted by cells in the testes.
Now, in an unexpected discovery, Vilain's team became the first to trace the SRY protein to a region of the brain called the substantia nigra, which deteriorates in Parkinson's disease.
Parkinson's disease occurs when cells in the substantia nigra begin to malfunction and die. These brain cells produce a neurotransmitter called dopamine that communicates with the brain areas controlling movement and coordination.
As the cells die off, they produce less dopamine. This slows the delivery of messages from the brain to the rest of the body, leaving the person unable to initiate or control their physical movements. The condition eventually leads to paralysis.
"For the first time, we've discovered that the brain cells that produce dopamine depend upon a sex-specific gene to function properly," Vilain said. "We've also shown that SRY plays a central role not just in the male genitals, but also in regulating the brain."
Vilain's lab used a rat model to study the effect of SRY on the brain. When the researchers lowered the level of
Source:University of California - Los Angeles