Y Chromosome DNA – The Genetics of Paternal Haplogroups
A Ychromosome DNA test (Y-DNA test) is a genealogical DNA test used to explore a man’s patrilineal or direct father’s-line ancestry.
Male ancestors carried their Y-DNA line along their migrations. Special sections on the Y chromosome determine a male’sY haplogroup, revealing the origins of his ancestors as evidenced by common DNA markers. Indeed, the human Y chromosome is normally unable to recombine with the Xchromosome, except for small pieces of pseudo-autosomal regions at the telomeres (which comprise about 5% of the chromosome’s length). These regions are relics of ancient homology between the X and Y chromosomes.Paternal haplogroups are thereof defined by mutations in the non-recombining potions of DNA from the Y Chromosome.
Because only males have a Y chromosome, in Y-Linked inheritance, a mutation can only be passed from father to son. As a result, only men can follow their paternal lineage. However, the woman could search for their paternal line from a DNA sample of paternal line male person (Fig9).