title: Loss of olfactory receptor function in hominin evolution.
abstract: The mammalian sense of smell is governed by the largest gene family, which encodes the olfactory receptors (ORs). The gain and loss of OR genes is typically correlated with adaptations to various ecological niches. Modern humans have 853 OR genes but 55% of these have lost their function. Here we show evidence of additional OR loss of function in the Neanderthal and Denisovan hominin genomes using comparative genomic methodologies. Ten Neanderthal and 8 Denisovan ORs show evidence of loss of function that differ from the reference modern human OR genome. Some of these losses are also present in a subset of modern humans, while some are unique to each lineage. Morphological changes in the cranium of Neanderthals suggest different sensory arrangements to that of modern humans. We identify differences in functional olfactory receptor genes among modern humans, Neanderthals and Denisovans, suggesting varied loss of function across all three taxa and we highlight the utility of using genomic information to elucidate the sensory niches of extinct species.
authors.affiliation: UCD School of Biology and Environmental Science, University College Dublin, Belfield, Dublin, Ireland ; UCD Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Belfield, Dublin, Ireland.
authors.forename: Graham M
authors.initials: GM
authors.lastname: Hughes
authors.affiliation: UCD School of Biology and Environmental Science, University College Dublin, Belfield, Dublin, Ireland.
authors.forename: Emma C
authors.initials: EC
authors.lastname: Teeling
authors.affiliation: UCD Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Belfield, Dublin, Ireland.
authors.forename: Desmond G
authors.initials: DG
authors.lastname: Higgins
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D005075:Biological Evolution; D030561:Databases, Nucleic Acid; D019143:Evolution, Molecular; D016678:Genome; D023281:Genomics; D015186:Hominidae / Q000235:genetics*; D006801:Humans; D008969:Molecular Sequence Data; D005810:Multigene Family; D018034:Olfactory Receptor Neurons / Q000378:metabolism*; D010802:Phylogeny; D018035:Receptors, Odorant / Q000737:chemistry / Q000145:classification / Q000235:genetics*; D016415:Sequence Alignment
chemical_list: D018035:Receptors, Odorant