Genetic counseling in Becker type X-linked muscular dystrophy. I. Theoretical considerations.

The prior probability of any woman being a carrier for Becker muscular dystrophy (BMD) has been calculated. If mu is the mutation rate in female germ cells and v the mutation rate in male germ cells, this probability is 34/3 mu + 20/3v. For all X-linked diseases with a fitness f the prior probability (H) is: (formula; see text).