In one of the latest issues of the Journal of the American Medical Association the results of a large cohort study with retrospective data collection were published. Researchers have shown no causal link between MMR vaccination and the development of autism spectrum disorder(ASD). American scientists have studied a large group of 95 727 children born in the years 2001-2007. Among them, children particularly vulnerable to ASD due to genetic predisposition, as their older siblings showed signs of autism spectrum disorders.