How do we arrive at the mutation rate assumption (.002 or .004) for our genealogical DNA studies?
It is very likely that each of the Y-chromosome microsatellite markers have different mutation rates. Since the current database of specific marker information is so small statistically, we are required to assume a standard mutation rate for all microsatellite markers until such time reliable individual mutation rates can be constructed for each marker. Currently the most accepted or standard rate is 1/500 = 0.002 which is the average pedigree rate across three significant reported studies–Heyer et al (1997), Bianchi et al (1998), and Kayser et al (2000). Some researchers choose to use a higher mutation rate of 1/250 = 0.004 which is considered by most geneticists as likely to underestimate (too short) the true times for the most recent common ancestor. This higher mutation rate is based on the reported study of Holtkemper et al (2001).
