THE ROLE OF GENETICS IN AGING AND DISEASES.

Scientists at the University of Georgia have shown that a hormone instrumental in the aging process is under genetic control, introducing a new pathway by which genetics regulates aging and disease. Earlier studies have found that blood levels of growth differentiation factor 11(GDF), decrease over time. Restoration of GDF11 reverses cardiovascular aging in old mice and leads to muscle and brain rejuvenation, a discovery that was listed as one of the top 10 breakthroughs in science in 2014. The discovery that GDF11 levels are under genetic control is of significant interest since it allows detection of genes responsible for GDF11 levels and its changes with age.The study confirmed results from previous experiments showing that GDF11 levels decrease over time and also showed that most of the depletion occurs by middle age. In addition, the study examined the relationship between GDF11 levels and markers of aging such as lifespan in 22 genetically diverse inbred mice strains. Of note, the strains with the highest GDF11 levels tended to live the longest. Gene mapping, was used by the team ,and they identified seven candidate genes that may determine blood GDF11 concentrations at middle age, demonstrating for the first time that GDF11 levels are highly heritable. Excerpts from the study "Circulating Concentrations of Growth Differentiation Factor 11 are heritable and correlate with life span,"