Another major bottleneck occurred about 5,000 years ago and subsequently most Eurasian men can trace their ancestry back to a dozen ancestors who lived 5,000 years ago.
The Y Chromosome Consortium (YCC) developed a system of naming major Y-DNA haplogroups with the capital letters A through T, with further subclades named using numbers and lower case letters (YCC longhand nomenclature).
In such cases, however, the possibility of misidentification is considered to be relatively high and some may belong to misidentified subclades of Haplogroup GHIJK.
Haplogroup G (M201) originated some 48,000 years ago and its most recent common ancestor likely lived 26,000 years ago in the Middle East. It is found in many ethnic groups in Eurasia; most common in the Caucasus, Iran, Anatolia and the Levant.
Haplogroup N possibly originated in eastern Asia and spread both west into Siberia and north, being the most common group found in some Uralic speaking peoples.
T-M184 is also found in significant minorities of Sciaccensi, Stilfser, Fulbe, Egyptians, Omanis, Sephardi Jews, The only living males reported to carry the basal paragroup K2* are indigenous Australians.
YCC shorthand nomenclature names Y-DNA haplogroups and their subclades with the first letter of the major Y-DNA haplogroup followed by a dash and the name of the defining terminal SNP.
Y-DNA haplogroup nomenclature is changing over time to accommodate the increasing number of SNPs being discovered and tested, and the resulting expansion of the Y-chromosome phylogenetic tree.
Because of this confusion, we introduced a shorthand version a few years ago that lists the branch of the tree and your terminal SNP, i.e. Therefore, in the very near term, Family Tree DNA will discontinue showing the current "longhand" on the tree and we will focus all of our discussions around your terminal defining SNP.
This changes no science – it just provides an easier and less confusing way for us all to communicate.