Sex‐specific demographic behaviours that shape human genomic variation

Abstract

In the human species, the two uniparental genetic systems (mitochondrial DNA and Y chromosome) exhibit contrasting diversity patterns. It has been proposed that sexspecific behaviours, and in particular differences in migration rate between men and women, may explain these differences. The availability of high-density genomic data and the comparison of genetic patterns on autosomal and sex chromosomes at global and local scales allow a reassessment of the extent to which sex-specific behaviours shape our genome. In this article, we first review studies comparing the genetic patterns at uniparental and biparental genetic systems and assess the extent to which sex-specific migration processes explain the differences between these genetic systems. We show that differences between male and female migration rates matter, but that they are certainly not the only contributing factor. In particular, differences in effective population size between men and women are also likely to account for these differences. Then, we present and discuss three anthropological processes that may explain sex-specific differences in effective population size and thus human genomic variation: (i) variance in reproductive success arising from, for example, polygyny; (ii) descent rules; and (iii) transmission of reproductive success.

The Greeks in the West: genetic signatures of the Hellenic colonisation in southern Italy and Sicily

“…Interestingly this is one of the few cases of sex-biased gene flow skewed towards an increased male instead of female contribution. 44 It is obvious that such numbers refer to the colonists who arrived in East Sicily as inferred from the descendants still living today. It is also worth stressing here that such estimates should not be taken as absolute but considered as indicative of the scale of the contribution.…”

“…It is known that patrilocality is a commonplace in continental Italy and Sicily. This may have facilitated the diffusion of mtDNA variation at a larger scale than Y chromosome variation, thus lowering the probability of finding local female genetic signatures of the GC (the study by Heyer 44 but see the study by Marks 45 ).…”

Different kinds of genetic markers permit inference of Paleolithic and Neolithic expansions in humans

“…In Aimé et al, 4 it has been shown that these two types of markers sometimes provide different inferences on the demographic history of human populations, especially as females generally exhibit higher effective population sizes and higher migration rates than males. 5,6 Conversely, autosomal markers provide synthetic information about both maternal and paternal lineages. When these loci are carefully selected in order to avoid pairwise linkage disequilibria, they also offer the possibility to consider each of them as an independent replicate.…”

Complete mtDNA genomes of Filipino ethnolinguistic groups: a melting pot of recent and ancient lineages in the Asia-Pacific region

“…Apart from population genetic factors (isolation, genetic drift and migration), anthropological processes also affect NRY and mtDNA differentiation patterns. 41 Among these processes, the patrilocal residence rule can be responsible for greater NRY differentiation. However, the differentiation of FE groups based on mtDNA may in turn be explained by matrilocality.…”

“…As with genetic differentiation, N e can also be affected by anthropological processes. 41 In the case of Table 8) and is the last of a series of CA that started with 18 reference data set groups (Supplementary Table 7; Supplementary Figure 7). FE group and reference data set group names are indicated in bold print.…”