New research may lead to breakthrough treatment of the skin-pigmentation disorder called vitiligo. A study published today in The New England Journal of Medicine also questions the common belief that people with vitiligo are more likely to contract melanoma.
The research, led by a team from the University of Colorado School of Medicine, establishes that vitiligo is an automimmune disease, in which the body attacks itself. That discovery points the way to treatment.
The findings were embraced by Vitiligo Support International, which played a key role in the study by helping to recruit participants. “I firmly believe that this research will open doors not only for vitiligo patients, but for many millions more suffering with other autoimmune diseases.,” said Jackie Gardner, Executive Director of the California-based group, which has 50,000 registered members.
Researchers, led by Richard A. Spritz, MD, who heads the Human Medical Genetics Program at the University of Colorado medical school, studied the genes of about 1500 people with vitiligo and compared them to the genes of 2800 people who did not have the disease. They used complex genetic-mapping equipment to test more than 579,000 DNA variations across the genome, called single-nucleotide polymorphisms, searching for gene differences that were associated with vitiligo Seven genes that showed up in people with vitiligo were associated with other autoimmune disorders such as Type I diabetes, multiple sclerosis and rheumatoid arthritis.
Vitiligo (vit-ill-EYE-go) affects about one-half to one percent of the population, perhaps 20,000 or more in Colorado. It is a difficult disease psychologically because it can be so obvious to others — lack of pigmentation causes white patches on the skin and scalp. Vitiligo occurs when the body attacks its own melanocytes, the cells that make pigment in the skin. Environmental factors probably play a role in triggering the disorder.
“This is by far the largest study of vitiligo ever done,” Spritz said. “That was made possible by cooperation among an international team of researchers and patient groups from around the world.”
The research, originally aimed at understanding what causes vitiligo, also has great importance for melanoma skin cancer.
“From a genetic standpoint, vitiligo and melanoma in some ways seem to be the opposite sides of the same coin,” Spritz said. “Some of the same genes that predispose to vitiligo protect from melanoma, and vice versa.” Spritz noted, “We think this may have something to do with the immune system scanning for and destroying early cancers, and may mean that people with vitiligo are less likely to develop melanoma.”
One of the international research collaborators, Dorothy Bennett, PhD, at St. George’s University of London, said that the findings reported in The New England Journal of Medicine point toward treatment of vitiligo that likely includes “an element of calming down the immune response. My prediction is that combining this with something to make the remaining pigment cells divide faster, to fill the gaps, is what will work best.”