title: Mitochondrial DNA variation in an isolated area of Central Italy.
abstract: BACKGROUND
  The genetic variation in Italy is the result of ancient population movement, demographic change, and geography. The increasing possibility of studying the maternal genetic structure of selected Italian population samples at a high level of phylogenetic resolution provides a particularly useful model to assess the presence of genetic traces of the ancient people who lived in Italy in pre-Roman times in present populations
  
  
  OBJECTIVE
  In this study we reconstructed the genetic maternal history of Jenne and Vallepietra, two mountain communities in the Aniene Valley in the Simbruini Mountains near Rome. Both communities have been spared external invasion due to their geographic location, which very likely preserved the genetic pool of these autochthonous populations.
  
  
  METHODS
  The study population (124 individuals from Jenne and Vallepietra) were investigated for D-loop mtDNA hypervariable segments I (HVS-I) and II (HVS-II) and for informative single nucleotide polymorphisms (SNPs) within the coding region. The detected haplotypes were then compared with those of other Italian, European and Mediterranean populations.
  
  
  RESULTS
  The distribution of mtDNA diversity in Jenne and Vallepietra, although similar to that found in other European populations, shows a basic variability and the typical signs of a certain degree of isolation between them and other populations analysed; in particular, the Vallepietra sample showed an unusually high frequency (71.3%) of mtDNA haplogroups which are typical of Near Eastern and South-Western Asian populations.
  
  
  CONCLUSIONS
  The high degree of differentiation between the two villages is intriguing, since it suggests a low level of gene flow between them, despite their close geographic proximity and shared linguistic features. The degree of their genetic isolation, also in comparison to other Italian, European and Mediterranean populations, is consistent with isolation among geographically separated populations.
authors.affiliation: Dipartimento di Biologia, Università di Roma Tor Vergata, Via della Ricerca Scientifica n. 1, 00173 Rome, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Messina
authors.forename: Gabriele
authors.initials: G
authors.lastname: Scorrano
authors.forename: Cristina Martínez
authors.initials: CM
authors.lastname: Labarga
authors.forename: Mario Federico
authors.initials: MF
authors.lastname: Rolfo
authors.forename: Olga
authors.initials: O
authors.lastname: Rickards
mesh_terms: D004272:DNA, Mitochondrial / Q000235:genetics*; D004641:Emigration and Immigration; D019143:Evolution, Molecular; D005260:Female; D005787:Gene Frequency; D014644:Genetic Variation; D006239:Haplotypes; D006801:Humans; D007558:Italy; D008297:Male
chemical_list: D004272:DNA, Mitochondrial