title: The epigenetic side of human adaptation: hypotheses, evidences and theories.
abstract: BACKGROUND
  Epigenetics represents a still unexplored research field in the understanding of micro- and macro-evolutionary mechanisms, as epigenetic changes create phenotypic diversity within both individuals and populations.
  
  
  OBJECTIVE
  The purpose of this review is to dissect the landscape of studies focused on DNA methylation, one of the most described epigenetic mechanisms, emphasizing the aspects that could be relevant in human adaptations.
  
  
  METHODS
  Theories and results here considered were collected from the most recent papers published.
  
  
  RESULTS
  The matter of DNA methylation inheritance is here described as well as the recent evolutionary theories regarding the role of DNA methylation-and epigenetics in a broader sense-in human evolution. The complex relation between (1) DNA methylation and genetic variability and (2) DNA methylation and the environmental stimuli crucial in shaping genetic and phenotypic variability through the human lineage-such as diet, climate and pathogens exposure-are described. Papers about population epigenetics are also illustrated due to their high relevance in this context.
  
  
  CONCLUSIONS
  Genetic, epigenetic and phenotypic variations of the species, together with cultural ones, are considerably shaped by a vast range of environmental stimuli, thus representing the foundation of all human bio-cultural adaptations.
authors.affiliation: Department of Biological, Geological and Environmental Sciences, Laboratory of Molecular Anthropology and Centre for Genome Biology .
authors.forename: Cristina
authors.initials: C
authors.lastname: Giuliani
authors.forename: Maria Giulia
authors.initials: MG
authors.lastname: Bacalini
authors.forename: Marco
authors.initials: M
authors.lastname: Sazzini
authors.forename: Chiara
authors.initials: C
authors.lastname: Pirazzini
authors.forename: Claudio
authors.initials: C
authors.lastname: Franceschi
authors.forename: Paolo
authors.initials: P
authors.lastname: Garagnani
authors.forename: Donata
authors.initials: D
authors.lastname: Luiselli
mesh_terms: D000222:Adaptation, Physiological / Q000235:genetics*; D004247:DNA / Q000737:chemistry* / Q000235:genetics; D019175:DNA Methylation / Q000235:genetics*; D004032:Diet; D004777:Environment; D044127:Epigenesis, Genetic; D014644:Genetic Variation / Q000235:genetics; D006801:Humans
chemical_list: D004247:DNA
keywords: Adaptation; DNA methylation; environment; human evolution