Major histocompatibility complex class II compatibility, but not class I, predicts mate choice in a bird with highly developed olfaction

Abstract

Mate choice for major histocompatibility complex (MHC) compatibility has been found in several taxa, although rarely in birds. MHC is a crucial component in adaptive immunity and by choosing an MHCdissimilar partner, heterozygosity and potentially broad pathogen resistance is maximized in the offspring. The MHC genotype influences odour cues and preferences in mammals and fish and hence olfactorybased mate choice can occur. We tested whether blue petrels, Halobaena caerulea, choose partners based on MHC compatibility. This bird is long-lived, monogamous and can discriminate between individual odours using olfaction, which makes it exceptionally well suited for this analysis. We screened MHC class I and II B alleles in blue petrels using 454-pyrosequencing and quantified the phylogenetic, functional and allele-sharing similarity between individuals. Partners were functionally more dissimilar at the MHC class II B loci than expected from random mating (p ¼ 0.033), whereas there was no such difference at the MHC class I loci. Phylogenetic and non-sequence-based MHC allele-sharing measures detected no MHC dissimilarity between partners for either MHC class I or II B. Our study provides evidence of mate choice for MHC compatibility in a bird with a high dependency on odour cues, suggesting that MHC odour-mediated mate choice occurs in birds.

Genome-wide association analysis on five isolated populations identifies variants of the HLA-DOA gene associated with white wine liking

“…46 Another recent study conducted on monogamous birds with highly developed olfaction shows that it is MHC class II molecules and not class I, which determine mate recognition. 47 In humans it has been demonstrated that different HLA types show preference or dislike for specific scents, suggesting that some volatile molecules responsible for these odors are mimicking some HLA-specific scent. 48,49 MHC class II molecules are responsible for immune response to external stimuli and it is thus a more suitable candidate than class I MHC for a possible olfactory function.…”

Interactive effects of male and female age on extra-pair paternity in a socially monogamous seabird

“…In some passerine species, for example, structural plumage coloration, ultraviolet signals, and song performance correlate with male age and possibly influence female mate preferences (Siefferman and Hill 2005;Budden and Dickinson 2009;Kipper and Kiefer 2010), and foot color of blue-footed boobies is a dynamic sexually selected ornament that loses intensity with age (Torres and Velando 2003. Olfactory cues could also be used; mice and humans can use smell to discriminate between differently aged conspecifics (Mitro et al 2012), and some birds discriminate among conspecifics on the basis of their odor (Bonadonna and Nevitt 2004;Strandh et al 2012).…”

Odour-based discrimination of similarity at the major histocompatibility complex in birds

“…; range: 1 -4). Two individuals included in this study were only genotyped, using the method described in Strandh et al [9]. The correspondence between the two methods was tested by genotyping 36 individuals of the population using the two methods.…”

“…The blue petrel (Halobaena caerulea) is a monogamous seabird with a particularly good sense of smell [18][19][20] that has been shown to preferentially mate with partners dissimilar at the MHC class II loci [9]. In this monomorphic species, males and females share parental duties equally [21,22], and mate choice is therefore thought to be reciprocal.…”

“…Individuals with a broad antigen-binding repertoire can recognize and eliminate a wider range of pathogens and therefore have fitness advantages over individuals with a narrow MHC repertoire [1][2][3][4]. As MHC-dissimilar parents are more likely to produce offspring with a broad MHC repertoire, mating preference for MHC-dissimilar partners is a common strategy in numerous taxa, including mammals, fish, lizards and birds [5][6][7][8][9].…”