Human Y Chromosome Mutation Rate: Problems and Perspectives
Pp. 65-91 (27)
Paolo Francalacci, Daria Sanna and Antonella Useli
The information contained into the human genome is the result of a historic
process involving all the ancestors of a specific human being and it is a powerful tool
for reconstructing human evolution. Key information about human evolutionary history
can be robustly assembled from variation of the two haploid segments at uniparental
transmission: mitochondrial DNA and Y chromosome. These two genetic systems are
not subject to the rearrangement of recombination, and are inherited linearly through
generations, having mutation as the only possible source of variation. In particular, the
Y chromosome has been extensively studied for the study of human evolution. A major
goal of the evolutionary research is not only to elucidate the pathways of the human
peopling and the demographic changes that shaped the present populations, but also to
date these events. For this aim, the recognition of a correct mutation rate is crucial.
Genomic mutation rates can be estimated either by direct observation of mutations in
present-day families (de novo mutation rate), by calibrating genetic variation against
archaeological/historical records (evolutionary rate), or by using a sequence extracted
from ancient human remains of known chronology. In order to test whether the same
methodology could give consistent results when applied to different experimental
contexts, we applied the evolutionary rate based upon archaeological evidence to two
independent sets of data. Despite the striking difference in the absolute value of the
substitution rate, the TMRCA of corresponding nodes in the phylogenetic trees
obtained from the two databases are remarkably similar.
1000 genome project, Human evolution, Human population genetics,
Molecular clock, Mutation rate, Next Generation Sequencing, Phylogenetic trees,
Polymorphisms, Sardinian population, Single Nucleotide Y chromosome.
Dipartimento di Scienze della Natura e del Territorio, Università di Sassari, 07100 Sassari, Italy.