RESUMEN
The Middle East region is important to understand human evolution and migrations but is underrepresented in genomic studies. Here, we generated 137 high-coverage physically phased genome sequences from eight Middle Eastern populations using linked-read sequencing. We found no genetic traces of early expansions out-of-Africa in present-day populations but found Arabians have elevated Basal Eurasian ancestry that dilutes their Neanderthal ancestry. Population sizes within the region started diverging 15-20 kya, when Levantines expanded while Arabians maintained smaller populations that derived ancestry from local hunter-gatherers. Arabians suffered a population bottleneck around the aridification of Arabia 6 kya, while Levantines had a distinct bottleneck overlapping the 4.2 kya aridification event. We found an association between movement and admixture of populations in the region and the spread of Semitic languages. Finally, we identify variants that show evidence of selection, including polygenic selection. Our results provide detailed insights into the genomic and selective histories of the Middle East.
Asunto(s)
Genética de Población/historia , Genoma Humano , Animales , Cromosomas Humanos Y/genética , Bases de Datos Genéticas , Pool de Genes , Introgresión Genética , Geografía , Historia Antigua , Migración Humana , Humanos , Medio Oriente , Modelos Genéticos , Hombre de Neandertal/genética , Filogenia , Densidad de Población , Selección Genética , Análisis de Secuencia de ADNRESUMEN
X-chromosomal short tandem repeats (X-STRs) are used to complement autosomal and Y-STRs in complex kinship testing, and can be of potential value when determining trace female DNA in male background. We analyzed extracted and directly-amplified samples of 501 males from the United Arab Emirates and report the forensic statistical parameters of 12 X-STRs and haplotypes of the four previously defined linkage groups using the Investigator Argus X-12 QS kit. Combined PDM, PDF, MEC Desmarais Trio and MEC Desmarais Duo based on allele (and haplotype) frequencies were 0.9999999997 (0.999999996), >0.9999999999 (>0.999999999), 0.999999999 (0.999999996) and 0.9999997 (0.99999994) respectively. No shared profile was observed, and significant linkage disequilibrium was detected only within the four linkage groups. We calculated pairwise genetic distance (FST) between our Emirati sample and 35 populations and find they generally mirror biogeography and historical relationships. We identified 20 distinct off-ladder alleles in seven loci, the majority of which at DXS10148 and DXS10134. Our analysis reveals that the 12 loci are informative and discriminatory in the Emirati population.