HLA-DQB1, reproduction and health in consanguineous and non-consanguineous families in Bangladesh

This study identified 12 HLA-DQB1 alleles and investigated reproduction and health of 44 non-consanguineous (NC) and 36 consanguineous (C) families in Bangladesh. Hair or buccal cell (mouthwash) samples, socio-demographic, reproduction and health information were collected from families. Allele identification was achieved for 336 individuals. Socio-demographic differences between NC and C families included dissimilar paternal occupations, uncertainty of offspring birth dataset/ages and marriage dates, and occurrences of first maternal menses. Parental consanguinity did not affect general health and reproduction in this community. Patrilineal consanguinity may also be a tradition in this community. Therefore, generational consanguinity may have previously purged deleterious HLA alleles from the gene pool. Bangladeshis did not preferentially choose mates with dissimilar HLA-DQB1 alleles. Neither parental HLA-DQB1 sharing nor particular alleles were associated with pregnancy loss, stillbirths or offspring mortality. However, an excess of homozygous offspring was detected compared to Mendelian segregation ratios by mating type. This excess may be a consequence of purging deleterious alleles from the gene pool, limited effects of HLA-DQB1 on fitness, assaying small groups and/or low population pathogen loads. Deviations from Hardy Weinberg Equilibrium were detected in NC and C groups and could be due to selection, genetic drift, non-random mating, illegitimate offspring production and/or a consequence of small sample size. A reduction of allelic diversity was observed in C families. Although HLA-DQB1 alleles were not associated with most diseases, HLA-DQB1*030302, *060101, *0602 and *0603 were associated with malaria resistance. Genome homozygosity may affect human health and reproduction over time, since decreases in genetic diversity over generations of close-kin marriage may reduce a population’s potential to adapt to future changes in their environment.EThOS - Electronic Theses Online ServiceGBUnited Kingdo