title: Choosy Wolves? Heterozygote Advantage But No Evidence of MHC-Based Disassortative Mating.
abstract: A variety of nonrandom mate choice strategies, including disassortative mating, are used by vertebrate species to avoid inbreeding, maintain heterozygosity and increase fitness. Disassortative mating may be mediated by the major histocompatibility complex (MHC), an important gene cluster controlling immune responses to pathogens. We investigated the patterns of mate choice in 26 wild-living breeding pairs of gray wolf (Canis lupus) that were identified through noninvasive genetic methods and genotyped at 3 MHC class II and 12 autosomal microsatellite (STR) loci. We tested for deviations from random mating and evaluated the covariance of genetic variables at functional and STR markers with fitness proxies deduced from pedigree reconstructions. Results did not show evidences of MHC-based disassortative mating. Rather we found a higher peptide similarity between mates at MHC loci as compared with random expectations. Fitness values were positively correlated with heterozygosity of the breeders at both MHC and STR loci, whereas they decreased with relatedness at STRs. These findings may indicate fitness advantages for breeders that, while avoiding highly related mates, are more similar at the MHC and have high levels of heterozygosity overall. Such a pattern of MHC-assortative mating may reflect local coadaptation of the breeders, while a reduction in genetic diversity may be balanced by heterozygote advantages.
authors.affiliation: From the Laboratorio di genetica, ISPRA, via Cà Fornacetta 9, 40064 Ozzano dell'Emilia (Bologna), Italy (Galaverni, Caniglia, Milanesi, Fabbri, and Randi); Department of Biological, Geological and Environmental Sciences (BiGeA), University of Bologna, Via Selmi 3, 40126 Bologna, Italy (Lapalombella); and Department 18/Section of Environmental Engineering, Aalborg University, 9220 Aalborg, Denmark (Randi). marco.galaverni@isprambiente.it.
authors.forename: Marco
authors.initials: M
authors.lastname: Galaverni
authors.affiliation: From the Laboratorio di genetica, ISPRA, via Cà Fornacetta 9, 40064 Ozzano dell'Emilia (Bologna), Italy (Galaverni, Caniglia, Milanesi, Fabbri, and Randi); Department of Biological, Geological and Environmental Sciences (BiGeA), University of Bologna, Via Selmi 3, 40126 Bologna, Italy (Lapalombella); and Department 18/Section of Environmental Engineering, Aalborg University, 9220 Aalborg, Denmark (Randi).
authors.forename: Romolo
authors.initials: R
authors.lastname: Caniglia
authors.affiliation: From the Laboratorio di genetica, ISPRA, via Cà Fornacetta 9, 40064 Ozzano dell'Emilia (Bologna), Italy (Galaverni, Caniglia, Milanesi, Fabbri, and Randi); Department of Biological, Geological and Environmental Sciences (BiGeA), University of Bologna, Via Selmi 3, 40126 Bologna, Italy (Lapalombella); and Department 18/Section of Environmental Engineering, Aalborg University, 9220 Aalborg, Denmark (Randi).
authors.forename: Pietro
authors.initials: P
authors.lastname: Milanesi
authors.affiliation: From the Laboratorio di genetica, ISPRA, via Cà Fornacetta 9, 40064 Ozzano dell'Emilia (Bologna), Italy (Galaverni, Caniglia, Milanesi, Fabbri, and Randi); Department of Biological, Geological and Environmental Sciences (BiGeA), University of Bologna, Via Selmi 3, 40126 Bologna, Italy (Lapalombella); and Department 18/Section of Environmental Engineering, Aalborg University, 9220 Aalborg, Denmark (Randi).
authors.forename: Silvana
authors.initials: S
authors.lastname: Lapalombella
authors.affiliation: From the Laboratorio di genetica, ISPRA, via Cà Fornacetta 9, 40064 Ozzano dell'Emilia (Bologna), Italy (Galaverni, Caniglia, Milanesi, Fabbri, and Randi); Department of Biological, Geological and Environmental Sciences (BiGeA), University of Bologna, Via Selmi 3, 40126 Bologna, Italy (Lapalombella); and Department 18/Section of Environmental Engineering, Aalborg University, 9220 Aalborg, Denmark (Randi).
authors.forename: Elena
authors.initials: E
authors.lastname: Fabbri
authors.affiliation: From the Laboratorio di genetica, ISPRA, via Cà Fornacetta 9, 40064 Ozzano dell'Emilia (Bologna), Italy (Galaverni, Caniglia, Milanesi, Fabbri, and Randi); Department of Biological, Geological and Environmental Sciences (BiGeA), University of Bologna, Via Selmi 3, 40126 Bologna, Italy (Lapalombella); and Department 18/Section of Environmental Engineering, Aalborg University, 9220 Aalborg, Denmark (Randi).
authors.forename: Ettore
authors.initials: E
authors.lastname: Randi
mesh_terms: D000483:Alleles; D000818:Animals; D056084:Genetic Fitness; D014644:Genetic Variation; D005828:Genetics, Population; D005838:Genotype; D006579:Heterozygote; D007558:Italy; D008285:Major Histocompatibility Complex / Q000235:genetics*; D052586:Mating Preference, Animal; D018895:Microsatellite Repeats; D008957:Models, Genetic; D012098:Reproduction / Q000235:genetics; D019596:Wolves / Q000235:genetics* / Q000502:physiology
keywords: Canis lupus; fitness; major histocompatibility complex; mate choice; microsatellites; sexual selection