title: Molecular biomarkers for chronological age in animal ecology.
abstract: The chronological age of an individual animal predicts many of its biological characteristics, and these in turn influence population-level ecological processes. Animal age information can therefore be valuable in ecological research, but many species have no external features that allow age to be reliably determined. Molecular age biomarkers provide a potential solution to this problem. Research in this area of molecular ecology has so far focused on a limited range of age biomarkers. The most commonly tested molecular age biomarker is change in average telomere length, which predicts age well in a small number of species and tissues, but performs poorly in many other situations. Epigenetic regulation of gene expression has recently been shown to cause age-related modifications to DNA and to cause changes in abundance of several RNA types throughout animal lifespans. Age biomarkers based on these epigenetic changes, and other new DNA-based assays, have already been applied to model organisms, humans and a limited number of wild animals. There is clear potential to apply these marker types more widely in ecological studies. For many species, these new approaches will produce age estimates where this was previously impractical. They will also enable age information to be gathered in cross-sectional studies and expand the range of demographic characteristics that can be quantified with molecular methods. We describe the range of molecular age biomarkers that have been investigated to date and suggest approaches for developing the newer marker types as age assays in nonmodel animal species.
authors: Australian Antarctic Division, 203 Channel Highway, Kingston, Tas., 7050, Australia.
authors: Simon N
authors: SN
authors: Jarman
authors: Australian Antarctic Division, 203 Channel Highway, Kingston, Tas., 7050, Australia.
authors: Andrea M
authors: AM
authors: Polanowski
authors: Australian Antarctic Division, 203 Channel Highway, Kingston, Tas., 7050, Australia.
authors: Cassandra E
authors: CE
authors: Faux
authors: Center for Coastal Studies, 5 Holway Avenue, Provincetown, MA, 02657, USA.
authors: Jooke
authors: J
authors: Robbins
authors: Australian Antarctic Division, 203 Channel Highway, Kingston, Tas., 7050, Australia.|Institute of Marine and Antarctic Studies, University of Tasmania, Castray Esplanade, Hobart, Tas., 7000, Australia.
authors: Ricardo
authors: R
authors: De Paoli-Iseppi
authors: Marine Laboratory, Commonwealth Scientific and Industrial Research Organisation, Castray Esplanade, Hobart, Tas., 7000, Australia.
authors: Mark
authors: M
authors: Bravington
authors: Australian Antarctic Division, 203 Channel Highway, Kingston, Tas., 7050, Australia.
authors: Bruce E
authors: BE
authors: Deagle
mesh_terms: D000375:Aging / Q000235:genetics*; D000818:Animals; D015415:Biomarkers; D004463:Ecology / Q000379:methods; D044127:Epigenesis, Genetic; D006801:Humans; D016615:Telomere / Q000648:ultrastructure
chemical_list: D015415:Biomarkers
keywords: DNA methylation; epigenetic; gerontology; kinship; miRNA