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An epidemic of Ebola virus disease of unprecedented scale has been ongoing for more than a year in West Africa. As of 29 April 2015, there have been 26,277 reported total cases (of which 14,895 have been laboratory confirmed) resulting in 10,899 deaths. The source of the outbreak was traced to the prefecture of Guéckédou in the forested region of southeastern Guinea. The virus later spread to the capital, Conakry, and to the neighbouring countries of Sierra Leone, Liberia, Nigeria, Senegal and Mali. In March 2014, when the first cases were detected in Conakry, the Institut Pasteur of Dakar, Senegal, deployed a mobile laboratory in Donka hospital to provide diagnostic services to the greater Conakry urban area and other regions of Guinea. Through this process we sampled 85 Ebola viruses (EBOV) from patients infected from July to November 2014, and report their full genome sequences here. Phylogenetic analysis reveals the sustained transmission of three distinct viral lineages co-circulating in Guinea, including the urban setting of Conakry and its surroundings. One lineage is unique to Guinea and closely related to the earliest sampled viruses of the epidemic. A second lineage contains viruses probably reintroduced from neighbouring Sierra Leone on multiple occasions, while a third lineage later spread from Guinea to Mali. Each lineage is defined by multiple mutations, including non-synonymous changes in the virion protein 35 (VP35), glycoprotein (GP) and RNA-dependent RNA polymerase (L) proteins. The viral GP is characterized by a glycosylation site modification and mutations in the mucin-like domain that could modify the outer shape of the virion. These data illustrate the ongoing ability of EBOV to develop lineage-specific and potentially phenotypically important variation.

The possible factors involved in the generation of p49a,f TaqI Y-chromosome spatial diversity in Egypt were explored. The object was to consider explanations beyond those that emphasize gene flow mediated via military campaigns within the Nile corridor during the dynastic period. Current patterns of the most common variants (V, XI, and IV) have been suggested to be primarily related to Middle Kingdom and New Kingdom political actions in Nubia, including occasional settler colonization, and the conquest of Egypt by Kush (in upper Nubia, northern Sudan), thus initiating the Twenty-Fifth Dynasty. However, a synthesis of evidence from archaeology, historical linguistics, texts, distribution of haplotypes outside Egypt, and some demographic considerations lends greater support to the establishment, before the Middle Kingdom, of the observed distributions of the most prevalent haplotypes V, XI, and IV. It is suggested that the pattern of diversity for these variants in the Egyptian Nile Valley was largely the product of population events that occurred in the late Pleistocene to mid-Holocene through the First Dynasty, and was sustained by continuous smaller-scale bidirectional migrations/interactions. The higher frequency of V in Ethiopia than in Nubia or upper (southern) Egypt has to be taken into account in any discussion of variation in the Nile Valley., (Copyright 2005 Wiley-Liss, Inc)

What is the relationship between the patterns of biological and sociocultural variation in extant humans? Is this relationship accurately described, or best explained, by the term 'race' and the schema of 'racial' classification? What is the relationship between 'race', genetics and the demographic groups of society? Can extant humans be categorized into units that can scientifically be called 'races'? These questions underlie the discussions that address the explanations for the observed differences in many domains between named demographic groups across societies. These domains include disease incidence and prevalence and other variables studied by biologists and social scientists. Here, we offer a perspective on understanding human variation by exploring the meaning and use of the term 'race' and its relationship to a range of data. The quest is for a more useful approach with which to understand human biological variation, one that may provide better research designs and inform public policy.