Impact of societal and legal context on the blood supply of African-ancestry populations in Western countries: A review of practices and the French example.

In Western countries, blood supply agencies encounter impediments in providing blood groups defined as rare or of interest, notably for sub-Saharan African ancestry (SSAA) recipients. To establish warning levels and anticipate future blood needs, an estimate of the current carriers of rare blood groups, both potential patients or donors, is crucial but complex. Indeed, if the strict needs can be estimated in medical terms, the modalities of blood product collection must be considered from an interdisciplinary perspective, at the interface of biological data and social norms. Here, we aim to understand how legal choices and a set of representations of otherness may influence the supply of rare blood for SSAA populations. After examining these issues, considering different norms and limits that govern French society, we compare this data with those of four Western countries facing the same difficulties (United States, United Kingdom, Italy and the Netherlands). This work began as part as the reflections of Social Lab, an institutional programme created by the French Blood Establishment (EFS). How can we effectively improve the qualitative blood coverage for SSAA populations? There is no unique solution, but there are many more or less effective answers. Comparison across countries reveals a strong influence of the socio-political histories and ethical choices before technical and medical considerations. We consider that an institutional policy is required to resolve recruitment issues of SSAA donors sustainably. Lastly, we introduce a working group called the EFS Social Lab, which aims to set up a monitoring mechanism for donors and societal trends to make blood donation effective.

Genes flow by the channels of culture: the genetic imprint of matrilocality in Ngazidja, Comoros Islands.

Post-marital residence of spouses is one of the architects of population genetic structure. In the present study, we tested how the place of residence of males and females in Ngazidja, Comoros Islands, has unequally channeled, by dispersal among villages, the male and female genetic diversity. Using sequences of the hypervariable segment I of the mitochondrial DNA (mtDNA HVS-I) and six Y-chromosome microsatellites (Y-STRs), we measured the genetic variation and male-to-female effective number of migrants ratios based on FST values and revealed a genetic structure mostly driven by male gene flow across villages. This genetic feature illustrates the uxori-matrilocality inherited from the Bantu expansion, though one exception exists in Bandamadji whose historically documented military status implied patrilocality in this locality.