Characteristics of the Y chromosome and the Y chromosome phylogenetic tree.

A) The abridged general view of stable inheritance of the Y chromosome among male generations. Recombination between homologous chromosomes are existed in other chromosomes. B) Illustration diagram of the SNP inheritance on the Y chromosome. Each color star represents a new SNP, and it can be inherited to the next generation. C) The abbreviated form of the Y chromosome phylogenetic tree. Haplogroup E and O were selected for this study. D) The tree of haplogroup O and its subgroups in Han Chinese population. The methylation patterns of bold labeled subclades are studied.