Two Genes Newly Associated with Familial Pulmonary Fibrosis

Researchers at the University of Texas (UT) Southwestern Medical Center have identified mutations in two genes that cause a fatal lung-scarring disease known as familial pulmonary fibrosis. Researchers also determined that these mutations cause excessive shortening of telomeres. Telomeres are repetitive sequences of DNA that protect the ends of chromosomes from deteriorating. Telomeres are sometimes compared to the plastic ends of shoelaces, which protect shoelaces from fraying. Together, the two mutated genes − PARN and RTEL1 − explain about seven percent of familial pulmonary fibrosis and strengthen the link between lung fibrosis and telomere dysfunction, according to the study, which was done in conjunction with the Yale Center for Genome Analysis, and is published in the May 2015 issue of Nature Genetics. The article is titled “Exome Sequencing Links Mutations in PARN and RTEL1 with Familial Pulmonary Fibrosis and Telomere Shortening.” “Although RTEL1 had been previously linked to telomere biology, our finding that PARN was involved in telomere regulation and human disease was completely unexpected,” said senior author Dr. Christine Kim Garcia (photo), M.D., Ph.D., Associate Professor of Internal Medicine and with the Eugene McDermott Center for Human Growth and Development. Approximately 50,000 people in the United States annually develop idiopathic pulmonary fibrosis, a progressive disease that principally affects the elderly, according to the Pulmonary Fibrosis Foundation. Approximately one in 20 people have a close relative with the disease, in which case they themselves are considered to possibly have familial pulmonary fibrosis. Without a lung transplant, pulmonary fibrosis patients typically die within three years of diagnosis.