Y Haplogroup Diversity of the Dominican Republic: Reconstructing the Effect of the European Colonization and the Trans-Atlantic Slave Trades.

The Dominican Republic is one of the two countries on the Hispaniola island, which is part of the Antilles. Hispaniola was affected by the European colonization and massive deportation of African slaves since the XVI century and these events heavily shaped the genetic composition of the present-day population. To shed light about the effect of the European rules, we analyzed 92 single nucleotide polymorphisms on the Y chromosome in 182 Dominican individuals from three different locations.

Rapidly mutating Y-STRs in rapidly expanding populations: Discrimination power of the Yfiler Plus multiplex in northern Africa.

The male-specific northern African genetic pool is characterised by a high frequency of the E-M81 haplogroup, which expanded in very recent times (2-3 kiloyears ago). As a consequence of their recent coalescence, E-M81 chromosomes often cannot be completely distinguished on the basis of their Y-STR profiles, unless rapidly-mutating Y-STRs (RM Y-STRs) are analysed. In this study, we used the Yfiler® Plus kit, which includes 7 RM Y-STRs and 20 standard Y-STR, to analyse 477 unrelated males coming from 11 northern African populations sampled from Morocco, Algeria, Libya and Egypt.

The peopling of the last Green Sahara revealed by high-coverage resequencing of trans-Saharan patrilineages.

Background: Little is known about the peopling of the Sahara during the Holocene climatic optimum, when the desert was replaced by a fertile environment.

Results: In order to investigate the role of the last Green Sahara in the peopling of Africa, we deep-sequence the whole non-repetitive portion of the Y chromosome in 104 males selected as representative of haplogroups which are currently found to the north and to the south of the Sahara. We identify 5,966 mutations, from which we extract 142 informative markers then genotyped in about 8,000 subjects from 145 African, Eurasian and African American populations.

Forensic data and microvariant sequence characterization of 27 Y-STR loci analyzed in four Eastern African countries.

By using the recently introduced 6-dye Yfiler Plus multiplex, we analyzed 462 males belonging to 20 ethnic groups from four eastern African countries (Eritrea, Ethiopia, Djibouti and Kenya). Through a Y-STR sequence analysis, combined with 62 SNP-based haplogroup information, we were able to classify observed microvariant alleles at four Y-STR loci as either monophyletic (DYF387S1 and DYS458) or recurrent (DYS449 and DYS627). We found evidence of non-allelic gene conversion among paralogous STRs of the two-copy locus DYF387S1.

Evidence of extensive non-allelic gene conversion among LTR elements in the human genome.

Long Terminal Repeats (LTRs) are nearly identical DNA sequences found at either end of Human Endogenous Retroviruses (HERVs). The high sequence similarity that exists among different LTRs suggests they could be substrate of ectopic gene conversion events. To understand the extent to which gene conversion occurs and to gain new insights into the evolutionary history of these elements in humans, we performed an intra-species phylogenetic study of 52 LTRs on different unrelated Y chromosomes.