Estimation of Recent and Ancient Inbreeding in a Small Endogamous Tunisian Community Through Genomic Runs of Homozygosity

Abstract : Runs of homozygosity (ROHs) are extended genomic regions of homozygous genotypes that record populations' mating patterns in the past. We performed microarray genotyping on 15 individuals from a small isolated Tunisian community. We estimated the individual and population genome-wide level of homozygosity from data on ROH above 0.5 Mb in length. We found a high average number of ROH per individual (48.2). The smallest ROH category (0.5-1.49 Mb) represents 0.93% of the whole genome, while medium-size (1.5-4.99 Mb) and long-size ROH (>= 5 Mb) cover 1.18% and 0.95%, respectively. We found that genealogical individual inbreeding coefficients (Fped) based on three-to four-generation pedigrees are not reliable indicators of the current proportion of genome-wide homozygosity inferred from ROH (FROH) either for 0.5 or 1.5 Mb ROH length thresholds, while identity-by-descent sharing is a function of shared coancestry. This study emphasizes the effect of reproductive isolation and a prolonged practice of consanguinity that limits the genetic heterogeneity. It also provides evidence of both recent and ancient parental relatedness contribution to the current level of genome-wide homozygosity in the studied population. These findings may be useful for evaluation of long-term effects of inbreeding on human health and for future applications of ROHs in identifying recessive susceptibility genes.
Type de document :
Article dans une revue
Annals of Human Genetics, Wiley, 2015, 79 (6), pp.402 - 417. 〈10.1111/ahg.12131〉
Liste complète des métadonnées

https://hal-riip.archives-ouvertes.fr/pasteur-01375019
Contributeur : Institut Pasteur Tunis <>
Soumis le : dimanche 2 octobre 2016 - 20:01:46
Dernière modification le : lundi 8 octobre 2018 - 17:44:08

Lien texte intégral

Identifiants

Collections

Citation

Nizar Ben Halim, Majdi Nagara, Béatrice Regnault, Sana Hsouna, Khaled Lasram, et al.. Estimation of Recent and Ancient Inbreeding in a Small Endogamous Tunisian Community Through Genomic Runs of Homozygosity. Annals of Human Genetics, Wiley, 2015, 79 (6), pp.402 - 417. 〈10.1111/ahg.12131〉. 〈pasteur-01375019〉

Partager

Métriques

Consultations de la notice

132