Population-Genetic Influences on Genomic Estimates of the Inbreeding Coefficient: A Global Perspective

Abstract

Background/Aims: Culturally driven marital practices provide a key instance of an interaction between social and genetic processes in shaping patterns of human genetic variation, producing, for example, increased identity by descent through consanguineous marriage. A commonly used measure to quantify identity by descent in an individual is the inbreeding coefficient, a quantity that reflects not only consanguinity, but also other aspects of kinship in the population to which the individual belongs. Here, in populations worldwide, we examine the relationship between genomic estimates of the inbreeding coefficient and population patterns in genetic variation. Methods: Using genotypes at 645 microsatellites, we compare inbreeding coefficients from 5,043 individuals representing 237 populations worldwide to demographic consanguinity frequency estimates available for 26 populations as well as to other quantities that can illuminate population-genetic influences on inbreeding coefficients. Results: We observe higher inbreeding coefficient estimates in populations and geographic regions with known high levels of consanguinity or genetic isolation and in populations with an increased effect of genetic drift and decreased genetic diversity with increasing distance from Africa. For the small number of populations with specific consanguinity estimates, we find a correlation between inbreeding coefficients and consanguinity frequency (r = 0.349, p = 0.040). Conclusions: The results emphasize the importance of both consanguinity and population-genetic factors in influencing variation in inbreeding coefficients, and they provide insight into factors useful for assessing the effect of consanguinity on genomic patterns in different populations.

The Churches' Bans on Consanguineous Marriages, Kin-Networks and Democracy

“…Nevertheless, evidence from countries that have data based on different sources suggest consistency over time and sampling method. Studies comparing Bitles's data to genetic correlates of inbreeding find that both methods paint a consistent picture (Leutenegger et al, 2011, Pemberton andRosenberg, 2014).…”

Observed and expected frequencies of structural hemoglobin variants in newborn screening surveys in Africa and the Middle East: deviations from Hardy-Weinberg equilibrium

“…33 Differences in the presumed frequency of inbreeding suggested by the F IS coefficient often reflect the influences of genetic isolation and genetic drift, including past population bottlenecks and founder effects rather than consanguineous marriage. 37 Differences in the F IS coefficient may also reflect differences in study quality, including mistaken attribution of genotype due to testing errors and selection bias. A study that analyzed data from 26 populations around the world with both F IS coefficients and estimates of consanguinity found that the latter explained a little more than one-tenth of variation in the former (r = 0.349, p = 0.040).…”

“…A study that analyzed data from 26 populations around the world with both F IS coefficients and estimates of consanguinity found that the latter explained a little more than one-tenth of variation in the former (r = 0.349, p = 0.040). 37 …”

Endogamy and suicide: An observation-based hypothesis

“…by calculating the number of individuals born outside the small community as was done in Palawan. Measures of endogamy may also been done [5]. 4) The measure of particular genetic variations in high risk groups vs. control groups to confirm their common origin.…”

“…Endogamy is influenced by the size of the population and the level of isolation, in addition to legal, cultural and religious practices. Isolation, through its limitation of the number of potential spouses, is a major risk factor of endogamy, as shown by significant correlations between measures of genetic isolation and measures of inbreeding [5]. Endogamy has been associated with higher mortality and morbidity, including complex disorders like mental and behavioral disorders [3].…”