Data from: Heterozygosity at neutral and immune loci is not associated with neonatal mortality due to microbial infection in Antarctic fur seals

Numerous studies have reported correlations between the heterozygosity of
genetic markers and fitness. These heterozygosity fitness correlations
(HFCs) play a central role in evolutionary and conservation biology, yet
their mechanistic basis remains open to debate. For example, fitness
associations have been widely reported at both neutral and functional
loci, yet few studies have directly compared the two, making it difficult
to gauge the relative contributions of genome-wide inbreeding and
functional genetic variation to fitness. Here, we compared the effects of
neutral and immune gene heterozygosity on death from bacterial infection
in Antarctic fur seal (Arctocephalus gazella) pups. We specifically
developed a panel of 13 microsatellites from expressed immune genes and
genotyped these together with 48 neutral loci in 234 individuals,
comprising 39 pups that were classified at necropsy as having most likely
died of bacterial infection together with a five times larger matched
sample of healthy surviving pups. Identity disequilibrium quantified from
the neutral markers was positive and significant, indicative of variance
in inbreeding within the study population. However, multilocus
heterozygosity did not differ significantly between healthy and infected
pups at either class of marker, and little evidence was found for fitness
associations at individual loci. These results support a previous study of
Antarctic fur seals that found no effects of heterozygosity at nine
neutral microsatellites on neonatal survival, and thereby help to refine
our understanding of how HFCs vary across the life cycle. Given that
non-significant HFCs are underreported in the literature, we also hope
that our study will contribute towards a more balanced understanding of
the wider importance of this phenomenon.