Men who carry the CT clade have Y chromosomes with the SNP mutation M168, along with P9.1 and M294. These mutations are present in all modern human male lineages except A and B-M60, which are both found almost exclusively in Africa.
The most recent common male line ancestor (TMRCA) of all CT men today probably predated the recent African origin of modern humans, a migration in which some of his descendants participated. He is therefore thought to have lived in Africa before this proposed migration.[1][5][4] In keeping with the concept of "Y-chromosomal Adam" given to the patrilineal ancestor of all living humans, CT-M168 has therefore also been referred to in popularized accounts as being the lineage of "Eurasian Adam" or "Out of Africa Adam"; because, along with many African Y-lineages, all non-African Y-lineages descend from it.[8][7][6]
No male in paragroup CT* has ever been discovered in modern populations. This means that all males carrying this haplogroup are also defined as being in one of the several major branch clades. All known surviving descendant lineages of CT are in one of two major subclades, CF and DE. In turn, DE is divided into a predominantly Asia-distributed haplogroup D-CTS3946 and a predominantly Africa-distributed haplogroup E-M96, while CF is divided into an East Asian, Native American, and Oceanian haplogroup C-M130 and haplogroup F-M89, which dominates most non-African populations.[6]
GHIJK F1329/M3658/PF2622/YSC0001299, CTS2254/M3680/PF2657, FGC2045/Z12203 Throughout Eurasia; also The Americas; at low levels/among minorities in Africa and Oceania
G M201, P257 Primarily the Caucasus; also at low levels/among minorities in Europe, North Africa, South West Asia and Central Asia
HIJK Throughout Eurasia; also The Americas; at low levels/among minorities in Africa and Oceania
^Van Oven M, Van Geystelen A, Kayser M, Decorte R, Larmuseau HD (2014). "Seeing the wood for the trees: a minimal reference phylogeny for the human Y chromosome". Human Mutation. 35 (2): 187–91. doi:10.1002/humu.22468. PMID24166809. S2CID23291764.
^K-M2313*, which as yet has no phylogenetic name, has been documented in two living individuals, who have ethnic ties to India and South East Asia. In addition, K-Y28299, which appears to be a primary branch of K-M2313, has been found in three living individuals from India. See: Poznik op. cit.; YFull YTree v5.08, 2017, "K-M2335", and; PhyloTree, 2017, "Details of the Y-SNP markers included in the minimal Y tree" (Access date of these pages: 9 December 2017)
^ Haplogroup S, as of 2017, is also known as K2b1a. (Previously the name Haplogroup S was assigned to K2b1a4.)
^ Haplogroup M, as of 2017, is also known as K2b1b. (Previously the name Haplogroup M was assigned to K2b1d.)