Mutations that accumulate with age in somatic (non-reproductive) cells are thought to contribute to aging and cancer. But testing whether somatic mutations do increase with age has been difficult, since mutations differ from cell to cell. In a study published online on April 16 in Proceedings of the National Academy of Sciences, Jan Vijg, Ph.D., Lei Zhang, Ph.D., and Xiao Dong, Ph.D., looked for somatic mutations in human B lymphocytes across a wide age span—from newborns to centenarians. They used a recently developed method for sequencing the entire genomes of single cells. B lymphocytes play key roles in the immune response, and immune deficiency is a well-known hallmark of aging. The number of mutations--many in the functional part of the B cell genome--increased from hundreds in newborns to more than 3,000 in centenarians. The study is the first to show that the number of mutations accumulating in normal human somatic cells is high enough to cause adverse effects. Dr. Vijg is professor and chair of genetics, and the Lola and Saul Kramer Chair in Molecular Genetics at Einstein. Drs. Zhang and Dong are postdoctoral research fellows in the Vijg lab.
Posted on: Tuesday, May 21, 2019