As already mentioned, the preliminary results obtained for KIR genes at the worldwide scale suggest similar patterns to those found for HLA, but await confirmation through more thorough analyses. In this article, we have summarized our current knowledge of the polymorphism mTOR inhibitor of three immunogenetic complexes, GM, HLA and KIR, in relation to their diversity in human populations and the interpretation of that knowledge. Actually, these three genetic complexes represent a small fraction of our genome restricted to three different chromosomes. Likewise, studies of
mtDNA and Y-chromosome markers, which have proved to be highly informative to reconstruct gender-specific molecular phylogenies of the human species (refs 142, 143, among many others) also correspond to minor DNA fractions (∼ 0·0005% of the total haploid
genome, for mtDNA, and ∼ 2%, for the Y chromosome). By contrast, analyses of microsatellites and single nucleotide polymorphisms have provided relevant information on the entire genome (e.g. refs 144, 145). Impressive technical improvements now also allow high throughput DNA sequencing with promising genome-wide application to the study of human genetic variation worldwide, although this is still in the early stages. Therefore, the study of immunogenetic complexes may be seen as a limited contribution to our knowledge of human genome diversity. Another possible drawback of the analysis of immunogenetic markers in the field of anthropology Selleck MK-8669 is the fact that they are prone to natural selection, as discussed in the present review. As IgG, HLA and KIR molecules are instrumental in immune responses, their evolution is clearly influenced by environmental factors, which may
be a disadvantage when one tries to reconstruct the peopling history of modern humans. Indeed, Montelukast Sodium when selection is at work, the observed genetic relationships among human populations may not reflect their degree of historical relatedness, as can also be concluded for some highly variable phenotypic traits like human pigmentation.26,27 This would speak for neutral markers corresponding to non-coding regions of the genome, like microsatellites and single nucleotide polymorphisms, being preferred for genetic studies in anthropology. On the other hand, general conclusions drawn by analysing the patterns of genetic diversity of widely studied immunogenetic markers, like GM and HLA, are shown to be congruent with those found for other genetic markers. This is the case for at least five major results. 1 Of the total genetic diversity of the human species, the highest level of variation is found within populations, whereas inter-population variation represents only a minor proportion of the total genetic variance.