Common genetic disease linked to father's age

When this Noonan syndrome mutation arises in a normal sperm stem cell it makes that cell more likely to reproduce itself than stem cells lacking the mutation.

http://www.sciencedaily.com/releases/2013/06/130607131014.htm?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+sciencedaily%2Fhealth_medicine%2Fgenes+%28ScienceDaily%3A+Health+%26+Medicine+News+--+Genes%29