New genetic risk factor for developing autism spectrum disorder identified
To better understand the root causes, a n international team led by researchers at OHSU in Portland, Oregon has applied a new systematic analysis to a cohort of 2,300 families who have a single child affected with autism. The study focused on identifying and characterizing low-lying genetic mutations that may have been missed in previous research, given these mutations are only present in a fraction of the bulk DNA of an individual. Known as postzygotic mosaic mutations, or PMMs, these genetic changes occur after the conception of the human zygote during the development cycle of a fetus. An individual will contain a mosaic -- or assortment -- of mutated and non-mutated cells with the level of mosaicism depending on the time and location of the mutation's occurrence. This emerging class of genetic risk factors has recently been implicated in various neurologic conditions, however, their role in more complex disorders, such as autism, has been unclear. Autism risk due to unexp...