J1-M267 Y lineage marks climate-driven pre-historical human displacements

Abstract

The present day distribution of Y chromosomes bearing the haplogroup J1 M267*G variant has been associated with different episodes of human demographic history, the main one being the diffusion of Islam since the Early Middle Ages. To better understand the modes and timing of J1 dispersals, we reconstructed the genealogical relationships among 282 M267*G chromosomes from 29 populations typed at 20 YSTRs and 6 SNPs. Phylogenetic analyses depicted a new genetic background consistent with climate-driven demographic dynamics occurring during two key phases of human pre-history: (1) the spatial expansion of hunter gatherers in response to the end of the late Pleistocene cooling phases and (2) the displacement of groups of foragers/herders following the mid-Holocene rainfall retreats across the Sahara and Arabia. Furthermore, J1 STR motifs previously used to trace Arab or Jewish ancestries were shown unsuitable as diagnostic markers for ethnicity.

The key role of patrilineal inheritance in shaping the genetic variation of Dagestan highlanders

“…Time estimates were obtained 11 with BATWING, considering a constant-size population growth model. The time to the most recent common ancestor of a set of closely related Dagestan Y chromosomes belonging to haplogroup J1 was estimated to be 11 711 years (95% CI: 15 460-8930, using as priors a uniform distribution between germline and evolutionary estimated mutation rates and 25 years as intergeneration time).…”

“…7,8 Previous genetic studies have revealed that the Caucasian populations do not share the genetic variation believed by some researchers to be a signature of the Neolithic expansion through Europe, which has led some to infer that these populations are direct descendants of a more ancient Eurasian population. [9][10][11] Others suggest that the genetic legacy of the Caucasus region is mainly because of the people who crossed or invaded this territory in historic times. 12 A large amount of genetic data on the Caucasian populations, based on classical markers, 9,[13][14][15] Alu insertion polymorphisms, 10 mitochondrial DNA 10,16 and the non-recombining portion of the Y chromosome (NRY) 17 have shown that neither geography nor linguistics have had a strong influence on the genetic structure of these ethnic groups and that genetic drift appears to be the main factor acting in the region.…”

The emergence of Y-chromosome haplogroup J1e among Arabic-speaking populations

“…The majority of the samples were experimentally analyzed for the haplogroup J1e-defining SNP by either RFLP or DHPLC methodology, except for 55 reported as being of J1 membership from the Sudanese from Khartoum; Amhara from Addis Ababa, Ethiopia; and Iraqis from Nassiriya. 18 These were inferred to belong to J1e based on companion YSTR haplotype data. The criteria to deduce J1e status involved the filter of DYS388 Z15 repeats and YCAII A, B allele sizes of either 19, 22 or 22, 22.…”

“…18 Here, we present the phylogeographical and haplotype diversity data from a major sub-clade of J1-M267 that is defined by the J1e-Page08 (aka P58) SNP. 19,20 Hereafter, we shall refer to this major sub-clade as simply J1e.…”

Extensive genome-wide autozygosity in the population isolates of Daghestan

“…[30][31][32][33][34][35][36] Limited pedigree data suggest very high mean inbreeding coefficients (0.005-0.0134), 32,37 whereas population genetic studies have been restricted to autosomal Alu insertion and STR markers, the Y chromosome and mtDNA. 32,[37][38][39][40][41][42][43][44][45] …”