In a new study, researchers testing DNA in siblings with MS discovered a genetic variant in women that may increase risk of developing multiple sclerosis. According to study authors, the variant may be the one of the strongest genetic risk factors for MS discovered to date.
Researchers at the University of Illinois at Chicago were able to test three sisters among a group of five siblings between the ages of 23 and 26, all diagnosed with MS. What they found was a genetic change known as a single nucleotide polymorphism, or SNP – a change in a single base-pair of the DNA – in a gene called STK11, which plays a role in tumor suppression and is believed to have several roles in brain function. They found the variant in all three they tested.
To determine if the SNP could be a contributing factor to the siblings’ multiple sclerosis, the researchers screened DNA samples from 1,400 people – 750 with MS and 650 without – provided by Jorge Oksenberg at the University of California, San Francisco, who is a leading expert on the genetics of MS. They found that the SNP was 1.7 times as prevalent in women with MS as in women without the disease, making it one of the highest known genetic risk factors for MS.
Based on their analysis, the researchers estimate that the STK11 SNP is present in about 7 percent of the general population. But because far fewer people develop MS, other genetic or nongenetic factors must play a role in the development of the disease, said senior author Doug Feinstein, professor of anesthesiology at UIC and research biologist at the Jesse Brown VA Medical Center.
The variant occurs almost twice as often among women with MS as in women without the disease, making it “one of the strongest genetic risk factors for MS discovered to date,” said Feinstein.
The findings were published in the journal ASN Neuro.