Ireland and the USA while 2 were in Haplogroup G2a. The following gives a summary of most of the studies which specifically tested for M269, showing its distribution (as a percentage of total population) in Europe, North Africa, the Middle East and Central Asia as far as China and Nepal. The phylogeny of R-M269 according to ISOGG 2017: R1b1b (R-V88) R1b1b (PF6279/V88; previously R1b1a2) is defined by the presence of SNP marker V88, the discovery of which was announced in 2010 by Cruciani et al. Apart from individuals in southern Europe and Western Asia, the majority of R-V88 was found in the Sahel, especially among populations speaking Afroasiatic languages of the Chadic branch. Studies in 2005–08 reported "R1b*" at high levels in Jordan, Egypt and Sudan. Subsequent research by Myres et al. (2011) indicates that the samples concerned most likely belong to the subclade R-V88, which is now concentrated in Sub-Saharan Africa. According to Myres et al. (2011), this may be explained by a back-migration from Asia into Africa by R1b-carrying people. Gonzales et al. (2013), using more advanced techniques, indicate that it is equally probable that V88 originated in Central Africa and spread northward towards Asia. The patterns of diversity in African R1b-V88 did not seem to fit with a movement of Chadic-speaking people from the North, across the Sahara to West-Central Africa, but was compatible with the reverse. An origin of V88 lineages in Central Africa, followed by a migration to North Africa. However, Shriner, D., & Rotimi, C. N. (2018), associate the introduction of R1b into Chad, with the more recent movements of Baggara Arabs. D'Atanasio et al. (2018) propose that R1b-V88 originated in Europe about 12 000 years ago and crossed to North Africa by about 8000 years ago; it may formerly have been common in southern Europe, where it has since been replaced by waves of other haplogroups, leaving remnant subclades almost exclusively in Sardinia. It first radiated within Africa likely between 7 and 8 000 years ago – at the same time as trans-Saharan expansions within the unrelated haplogroups E-M2 and A-M13 – possibly due to population growth allowed by humid conditions and the adoption of livestock herding in the Sahara. R1b-V1589, the main subclade within R1b-V88, underwent a further expansion around 5500 years ago, likely in the Lake Chad Basin region, from which some lines recrossed the Sahara to North Africa. Marcus et