Friday 30 September 2005
Like mtDNA, there is no evidence for recombination in the non-recombining part of the Y chromosome (NRY).
The mutation rate of the NRY is comparable to that of nuclear DNA, which means that polymorphisms are more difficult to find but genealogies are easier to reconstruct.
The greater length of DNA on the NRY (perhaps 30 million bases of euchromatic DNA) relative to mtDNA compensates in data analyses for its lower mutation rate.
Even though the NRY behaves effectively as a single locus, which is usually insufficient for evolutionary analyses, it has provided results that are consistent across many studies and in agreement with many archeological findings.
In fact, the NRY genealogy constructed from 167 mutations has been replicated with a totally independent set of 114 mutations and confirmed independently using mostly different population samples.