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Combined use of biallelic and microsatellite Y-chromosome polymorphisms in finding affinities among African populations is discussed. Seven biallelic polymorphic sites were studied to define Y-chromosome haplotypes. Data was combined with those from four dinucleotide-repeat polymorphisms. The object was to establish Y-chromosome compound superhaplotypes. Geographic closeness seems better as a predictor of genetic affinity than language and genetic similarities.

mtDNA analysis shows that a significant population expansion from southwestern Europe into northeastern Europe took place during the Late Paleolithic, about 10,000-15,000 years ago. Haplogroup V acts as an mtDNA marker of the expansion, while haplogroup H also was spread. Other genetic evidence supports the expansion. Nine Eurasian populations, a total of 419 individuals, were studied for the mtDNA analysis.

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. The Dominican Y haplogroup composition was characterized by an excess of northern African/European lineages (59%), followed by the African clades (38%), whereas the Native-American lineages were rare (3%). The comparison with the mitochondrial DNA variability, dominated by African clades, revealed a sex-biased admixture pattern, in line with the colonial society dominated by European men. When other Caribbean and non-Caribbean former colonies were also considered, we noted a difference between territories under a Spanish rule (like the Dominican Republic) and British/French rule, with the former characterized by an excess of European Y lineages reflecting the more permissive Iberian legislation about mixed people and slavery. Finally, we analyzed the distribution in Africa of the Dominican lineages with a putative African origin, mainly focusing on central and western Africa, which were the main sources of African slaves. We found that most (83%) of the African lineages observed in Santo Domingo have a central African ancestry, suggesting that most of the slaves were deported from regions. [ABSTRACT FROM AUTHOR]

A correction to the article "Human Y Chromosome Haplogroup R-V88: A Paternal Genetic Record of Early Mid Holocene Trans-Saharan Connections and the Spread of Chadic Languages," that was published in the previous issue of the journal is presented.

Recently, the function of mitochondria in gametes and preimplantation preembryo has been highlighted by the diffusion and advancement of assisted reproductive technologies. Several attempts to generate heteroplasmic embryos and, recently, the birth of heteroplasmic babies have been reported. In this article, some aspects of the role of mitochondria in human reproduction and in assisted reproductive technologies are described, as well as our data about the survival of paternal mitochondria in babies born after intracytoplasmic sperm injection (ICSI) and in human embryos generated after ICSI. No evidence has been found for the transmission of paternal mitochondrial deoxyribonucleic acid (DNA) in offspring conceived with ICSI when spermatids have been used. Conversely, in embryos until the blastocyst stage, traces of paternal mitochondrial DNA have been observed. [ABSTRACT FROM AUTHOR]

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. We find that the coalescence age of the trans-Saharan haplogroups dates back to the last Green Sahara, while most northern African or sub-Saharan clades expanded locally in the subsequent arid phase., Conclusions: Our findings suggest that the Green Sahara promoted human movements and demographic expansions, possibly linked to the adoption of pastoralism. Comparing our results with previously reported genome-wide data, we also find evidence for a sex-biased sub-Saharan contribution to northern Africans, suggesting that historical events such as the trans-Saharan slave trade mainly contributed to the mtDNA and autosomal gene pool, whereas the northern African paternal gene pool was mainly shaped by more ancient events.