Data from: Strikingly high levels of heterozygosity despite 20 years of inbreeding in a clonal honey bee
Smith, Nicholas M. A. et al. (2020), Data from: Strikingly high levels of heterozygosity despite 20 years of inbreeding in a clonal honey bee, Dryad, Dataset, https://doi.org/10.5061/dryad.4pv2ft0
Inbreeding (the mating between closely related individuals) has detrimental effects that are associated with loss of heterozygosity at overdominant loci, and the expression of deleterious recessive alleles. However, determining which heterozygous loci are important for individual fitness, and the extent of their phenotypic effects remains poorly understood. Here, we utilise a unique inbred population of clonal (thelytokous) honey bees, Apis mellifera capensis, to determine which heterozygous loci are crucial for individual fitness. This population arose from a common ancestor approximately 20 years ago and has persisted for at least 100 generations. Thelytokous parthenogenesis results in a 1/3 of loss of heterozygosity with each generation. Yet, this clonal population retains heterozygosity throughout its genome due to selection against homozygotes. Deep sequencing of three sub-lineages of the population revealed that 3,766 of 10,884 genes (34%) have retained heterozygosity across all sub-lineages, suggesting that these genes have heterozygote advantage. The maintenance of heterozygosity in the same genes and genomic regions in all three sub-lineages suggests that nearly every chromosome carries genes that show sufficient heterozygote advantage to be selectively detrimental when homozygous.