A (Y-DNA)

This project is about a Y-haplogroup, which defines a group of men by a shared set of inherited features in the DNA of their Y-chromosome. This implies they have a patrilineal ancestor in common, because only males carry a Y-chromosome, which they inherit from their father. The major Y-haplogroups were formed thousands of years ago, and therefore each group can today include thousands to millions of men. For an introduction, you can visit the Y-DNA Haplogroups project, the DNA Testing project, or start at the beginning with the DNA Primer project.

Y-Haplogroup A is the set of Y-DNA haplogroups closest to the root of the human Y-DNA phylogenetic tree, "Y-chromosomal Adam" who is the most recent common male ancestor of all living humans. The designation "Y-haplogroup A" is a different from all other haplogroup names because it's understood to mean "all haplogroups that aren't descended from haplogroup BT-L413."

• Y-Haplogroup A @ Wikipedia
• Y-Haplogroup A @ ISOGG
• Y-DNA haplogroups @ Geni

Phylogeny

A simplified phylogeny of A haplogroups, from the ISOGG v12.1 (1-Jan-2017) Y-DNA tree, is:

• Y-chromosomal Adam
  • A00-AF6/L1284
  • A0-T-L1085
    • A0-CTS2809/L991
    • A1-P305
      • A1a-M31
      • A1b-P108
        • A1b1-L419/PF712
        • BT-M91 (aka A1b2-M91)

Subclades at Geni

The simple listing of A Y-haplogroups below was current as of 5 Jan 2017. After each haplogroup name is the number of profiles (for people living or deceased) who were assigned that haplogroup as of that day. Note that some haplogroup names are equivalent (e.g. A1a = A-M31) and all members of a haplogroup are also members of their ancestral haplogroup.

See the Y-DNA Geni Index project for a possibly more up-to-date listing.

• A (Y DNA) ...1,099
  • A-M202 (Y DNA) ...1
  • A-M31 (Y DNA) ...56
  • A-V148 (Y DNA) ...5
  • A1a (Y DNA) ...97
  • A1b1 (Y DNA) ...0
  • A3b2 (Y DNA) ...17