title: Inferring chronological age from DNA methylation patterns of human teeth.
abstract: OBJECTIVE
  Current methods to determine chronological age from modern and ancient remains rely on both morphological and molecular approaches. However, low accuracy and the lack of standardized protocols make the development of alternative methods for the estimation of individual's age even more urgent for several research fields, such as biological anthropology, biodemography, forensics, evolutionary genetics, and ancient DNA studies. Therefore, the aim of this study is to identify genomic regions whose DNA methylation level correlates with age in modern teeth.
  
  
  METHODS
  We used MALDI-TOF mass spectrometry to analyze DNA methylation levels of specific CpGs located in the ELOVL2, FHL2, and PENK genes. We considered methylation data from cementum, dentin and pulp of 21 modern teeth (from 17 to 77 years old) to construct a mathematical model able to exploit DNA methylation values to predict age of the individuals.
  
  
  RESULTS
  The median difference between the real age and that estimated using DNA methylation values is 1.20 years (SD = 1.9) if DNA is recovered from both cementum and pulp of the same modern teeth, 2.25 years (SD = 2.5) if DNA is recovered from dental pulp, 2.45 years (SD = 3.3) if DNA is extracted from cementum and 7.07 years (SD = 7.0) when DNA is recovered from dentin only.
  
  
  CONCLUSIONS
  We propose for the first time the evaluation of DNA methylation at ELOVL2, FHL2, and PENK genes as a powerful tool to predict age in modern teeth for anthropological applications. Future studies are needed to apply this method also to historical and relatively ancient human teeth.
authors.affiliation: Department of Biological, Geological and Environmental Sciences, Laboratory of Molecular Anthropology & Centre for Genome Biology, University of Bologna, Bologna, 40126, Italy.
authors.forename: Cristina
authors.initials: C
authors.lastname: Giuliani
authors.affiliation: Department of Cultural Heritage (DBC), Laboratories of Physical Anthropology and Ancient DNA, University of Bologna, Ravenna, 48121, Italy.
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Cilli
authors.affiliation: Department of Experimental, Diagnostic and Specialty Medicine (DIMES), University of Bologna, Bologna, 40126, Italy.|Interdepartmental Center "L. Galvani" (C.I.G.), University of Bologna, Bologna, 40126, Italy.
authors.forename: Maria Giulia
authors.initials: MG
authors.lastname: Bacalini
authors.affiliation: Department of Experimental, Diagnostic and Specialty Medicine (DIMES), University of Bologna, Bologna, 40126, Italy.|Interdepartmental Center "L. Galvani" (C.I.G.), University of Bologna, Bologna, 40126, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: Pirazzini
authors.affiliation: Department of Biological, Geological and Environmental Sciences, Laboratory of Molecular Anthropology & Centre for Genome Biology, University of Bologna, Bologna, 40126, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Sazzini
authors.affiliation: Department of Cultural Heritage (DBC), Laboratories of Physical Anthropology and Ancient DNA, University of Bologna, Ravenna, 48121, Italy.
authors.forename: Giorgio
authors.initials: G
authors.lastname: Gruppioni
authors.affiliation: Department of Experimental, Diagnostic and Specialty Medicine (DIMES), University of Bologna, Bologna, 40126, Italy.|Interdepartmental Center "L. Galvani" (C.I.G.), University of Bologna, Bologna, 40126, Italy.|IRCCS Institute of Neurological Sciences, Bologna, 40139, Italy.
authors.forename: Claudio
authors.initials: C
authors.lastname: Franceschi
authors.affiliation: Department of Experimental, Diagnostic and Specialty Medicine (DIMES), University of Bologna, Bologna, 40126, Italy.|Interdepartmental Center "L. Galvani" (C.I.G.), University of Bologna, Bologna, 40126, Italy.|Center for Applied Biomedical Research (CRBA), St. Orsola-Malpighi University Hospital, Bologna, Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Garagnani
authors.affiliation: Department of Biological, Geological and Environmental Sciences, Laboratory of Molecular Anthropology & Centre for Genome Biology, University of Bologna, Bologna, 40126, Italy.
authors.forename: Donata
authors.initials: D
authors.lastname: Luiselli
mesh_terms: D000123:Acetyltransferases / Q000235:genetics; D000293:Adolescent; D000328:Adult; D000366:Age Determination by Teeth / Q000379:methods*; D000368:Aged; D000885:Anthropology, Physical; D004247:DNA / Q000032:analysis / Q000737:chemistry* / Q000235:genetics* / Q000302:isolation & purification; D019175:DNA Methylation / Q000235:genetics*; D000081031:Fatty Acid Elongases; D006801:Humans; D008875:Middle Aged; D014070:Tooth / Q000737:chemistry*; D055815:Young Adult
chemical_list: C000630967:ELOVL2 protein, human; D004247:DNA; D000123:Acetyltransferases; D000081031:Fatty Acid Elongases
keywords: DNA methylation; ELOVL2; age-estimation; teeth