RESUMEN
Gene conversion and balancing selection have been invoked to explain the ubiquitous diversity of the antigen-presenting proteins encoded in the vertebrate major histocompatibility complex (MHC). In the present study, direct evidence for over-dominant selection promoting MHC diversity in primates is provided by the observation that, in a large free-ranging population of rhesus macaques, males heterozygous at MHC class II locus Mamu-DQB1 sired significantly more offspring than homozygotes (the male-specific selection coefficient s equals 0.34). This heterozygote advantage appeared to be independent of the actual male Mamu-DQB1 genotype. No similar effect emerged for a captive group of monkeys of similar genetic background but under veterinary care.
Asunto(s)
Genes MHC Clase II/genética , Heterocigoto , Reproducción/genética , Animales , Femenino , Genotipo , Homocigoto , Macaca mulatta , Masculino , Selección Genética , Conducta Sexual AnimalRESUMEN
Multilocus DNA fingerprinting with oligonucleotide probes (GTG)5, (GATA)4, and (CA)8 was applied in order to determine paternity in one birth cohort (15 infants) of social group (S) from the free-ranging colony of rhesus macaques (Macaca mulatta) on Cayo Santiago. While sires could be identified in 11 cases, all males tested (N = 19) could be excluded from paternity for the remaining four infants. Data revealed marked discrepancies between actual paternity and paternity as inferred from the observation of copulation behavior. Thus, a dominant social rank does not appear to be strongly associated with reproductive success. Furthermore, alternative reproductive strategies were found to yield comparable net benefits in reproduction. A second group of animals (M) was translocated from Cayo Santiago to the Sabana Seca Field Station in 1984. They have continuously resided together in a large outdoor enclosure since then. Here paternity assessment was seriously impeded by a reduced number of discriminating bands, i.e. offspring bands which were unequivocally derived from the sires. This was initially held to be indicative of a smaller degree of heterozygosity in Group M, and was attributed to inbreeding due to a lack of male immigration or extra-group fertilizations. However, a comparison of the DNA fingerprint patterns obtained in Group S and Group M lends only partial support to this idea.
Asunto(s)
Dermatoglifia del ADN , Macaca mulatta/genética , Animales , Animales Salvajes/genética , Secuencia de Bases , Femenino , Genética Conductual , Heterocigoto , Masculino , Datos de Secuencia Molecular , Sondas de Oligonucleótidos/genética , Paternidad , Puerto RicoRESUMEN
A description of the Cayo Santiago rhesus monkey (Macaca mulatta) colony is provided including an aerial photograph and map.