New York: Scientists have identified two statistically significant genetic variants that may lead to an increased risk of post-traumatic stress disorder (PTSD). Post-traumatic stress disorder is a mental health condition triggered by experiencing or seeing a terrifying event. "We found two notable genetic variants," said Murray.B.Stein, professor at University of California in the US. "The first was in a gene (ANKRD55) on chromosome 5 and the other variant was found on chromosome 19," he added. In previous research, this gene was also found to be associated with various autoimmune and inflammatory disorders, including multiple sclerosis, type II diabetes, celiac disease, and rheumatoid arthritis. Also, a genetic overlap was observed between PTSD and rheumatoid arthritis and psoriasis, the researchers said. The study, published online in JAMA Psychiatry, was conducted in a massive analysis of DNA samples from more than 13,000 US soldiers. "Further research will be needed to replicate the genome-wide significant association we found with the gene ANKRD55 and clarify the nature of the added another researcher Robert.J.Ursano, professor at Uniformed Services University in the US.