Isolates in a corridor of migrations: a high-resolution analysis of Y-chromosome variation in Jordan

Abstract

A high-resolution, Y-chromosome analysis using 46 binary markers has been carried out in two Jordan populations, one from the metropolitan area of Amman and the other from the Dead Sea, an area geographically isolated. Comparisons with neighboring populations showed that whereas the sample from Amman did not significantly differ from their Levantine neighbors, the Dead Sea sample clearly behaved as a genetic outlier in the region. Its high R1*-M173 frequency (40%) has until now only been found in northern Cameroonian samples. This contrasts with the comparatively low presence of J representatives (9%), which is the modal clade in Middle Eastern populations, including Amman. The Dead Sea sample also showed a high presence of E3b3a-M34 lineages (31%), which is only comparable to that found in Ethiopians. Although ancient and recent ties with sub-Saharan and eastern Africans cannot be discarded, it seems that isolation, strong drift, and/or founder effects are responsible for the anomalous Y-chromosome pool of this population. These results demonstrate that, at a fine scale, the smooth, continental clines detected for several Y-chromosome markers are often disrupted by genetically divergent populations.

Hypertension Prevalence, Awareness and Control Levels among Ghawarna: An African-Descendant Ethnic Minority in the Jordan Valley

“…First, Ghawarna have a distinct genetic background that is similar to that of Africans. 1,9,11 Epidemiological evidence confirms that HTN is more prevalent among Black populations compared with other population subgroups, 18,28 with low levels of detection, treatment, and control of HTN measured among Blacks. 14,19,27,29 This is also consistent with other studies that reported higher HTN prevalence, and poor awareness, treatment, and control rates among Afro-minorities in other parts of the world.…”

“…The former have a 'genetic isolate' that is clearly tied to Africa, but not the Eastern Mediterranean region, 10 and a "high level of [genetic] homogeneity" not found among other African communities around the world 11 especially subSaharan Africa. 9 Ghawarna live in scattered rural areas (villages) in the Jordan valley and around the Dead Sea area, which is about 400 meters below sea level. Some of these villages are considered Jordanian poverty pockets 13 where differences in the lifestyle and socioeconomic status compared with urban areas are Hypertension Status among Afro-Jordanians -Kheirallah et al evident.…”

“…1 This is in contrast to the Circassian and Chechen minorities who remain endogamous and relatively isolated in terms of culture and tradition. 8 Genetically, however, Ghawarna, [8][9][10][11] along with Circassian and Chechen, 12 represent a distinct population subgroup in Jordan. The former have a 'genetic isolate' that is clearly tied to Africa, but not the Eastern Mediterranean region, 10 and a "high level of [genetic] homogeneity" not found among other African communities around the world 11 especially subSaharan Africa.…”

Mitochondrial DNA and Y-chromosomal stratification in Iran: relationship between Iran and the Arabian Peninsula

“…41,42 Parental groups were assembled as specified in Table 1 for mtDNA and in Supplementary Table 2 for the Y-chromosome. 1,14,18,[43][44][45][46][47][48][49][50][51][52][53][54][55][56][57][58][59][60] To gauge significant deviations from neutral theory, 61 the Ewens-Watterson homozygosity test 62,63 was performed on Iranian mtDNA control region sequences (nucleotide positions 16 019-16 569). In addition, mtDNA control region sequence diversity was evaluated by nucleotide diversity index.…”

Y-chromosome distributions among populations in Northwest China identify significant contribution from Central Asian pastoralists and lesser influence of western Eurasians

“…However, the frequency of G-M201 largely reduced in West Asia, India and Pakistan. 31,32,57 Haplogroup G-M201 was detected in as few as five individuals from our three northwestern populations. H-M69 was an emerging marker during the second great human migration from Middle East into Indian subcontinent, with a supposed history of 25 000 years.…”