03 May 2018
THURSDAY, May 3, 2018 (HealthDay News) — Sometimes life’s sudden shocks or illnesses can turn hair gray — Barbara Bush, the former first lady who passed away in April, reportedly had her brown hair turn gray as a young mother, following a daughter’s tragic death. But how does premature graying happen? Scientists say new animal research may help clear up the mystery. The mouse studies suggest there’s a link between genes that contribute to hair and skin color and genes that alert the body about infections. “This new discovery suggests that genes that control pigment in hair and skin also work to control the innate immune system,” said study co-author William Pavan. “These results may enhance our understanding of hair graying,” he said. Pavan is chief of genetic disease research at the U.S. National Human Genome Research Institute. The study authors explained that when a body is under attack from a virus or bacteria, the innate immune system kicks into gear. However, the investigators said they were surprised by the link they found between immune system activation and hair pigmentation in the mice. The report was published online May 3 in the journal PLoS Biology. The study couldn’t prove a cause-and-effect relationship, and animal research often can’t be replicated in human studies. Still, “discovering this connection will help us understand pigmentation diseases with innate immune system involvement, like vitiligo,” Pavan said in a journal news release. Vitiligo is a condition that causes discolored skin patches. It affects less than 1 percent of people. Why rodents that are predisposed to go gray are more susceptible to changes in immune system signaling isn’t clear. The researchers said they will continue their studies to address this question. More information The U.S. National Institute of Arthritis and Musculoskeletal and Skin Diseases has more on vitiligo.
16 April 2018
MONDAY, April 16, 2018 (HealthDay News) — The color of your hair turns out to be a complicated thing, with a full 124 genes determining whether you wind up a blonde, brunette or redhead. The researchers who pinpointed the origins of hair hue said their findings could improve understanding of health conditions linked to pigmentation, including skin, testicular, prostate and ovarian cancers. For the study, investigators analyzed DNA data from nearly 300,000 people of European descent, along with information about their hair color. Using this information, the team identified 124 genes that play a major role in determining hair color. Of those genes, more than 100 were not previously known to influence pigmentation. “This work will impact several fields of biology and medicine. As the largest ever genetic study on pigmentation, it will improve our understanding of diseases like melanoma, an aggressive form of skin cancer,” said study co-lead author Tim Spector, a professor at King’s College London. “The genes that affect hair color also affect other cancer types, while other pigment genes affect the chances of having Crohn’s and other forms of bowel disease,” he added in a university news release. “Our work helps us to understand what causes human diversity in appearance by showing how genes involved in pigmentation subtly adapted to external environments and even social interactions during our evolution,” Spector said. “We found that women have significantly fairer hair than men, which reflects how important cultural practices and sexual preferences are in shaping our genes and biology,” Spector added. Co-lead author Manfred Kayser, a professor at Erasmus MC University Medical Center in Rotterdam, the Netherlands, said the finding could have yet another application. “Besides substantially increasing our understanding of human pigmentation genetics in general, finding these new hair color genes is also important for further increasing the accuracy of hair color prediction from DNA traces in future forensic applications, which can help to find unknown perpetrators of crime,” Kayser said. The study was published April 16 in the journal Nature Genetics. More information The U.S. National Human Genome Research Institute has more on DNA, genes and genomes.