title: MtDNA evidence for a genetic bottleneck in the early history of the Ashkenazi Jewish population.
abstract: The relative roles of natural selection and accentuated genetic drift as explanations for the high frequency of more than 20 Ashkenazi Jewish disease alleles remain controversial. To test for the effects of a maternal bottleneck on the Ashkenazi Jewish population, we performed an extensive analysis of mitochondrial DNA (mtDNA) hypervariable segment 1 (HVS-1) sequence and restriction site polymorphisms in 565 Ashkenazi Jews from different parts of Europe. These patterns of variation were compared with those of five Near Eastern (n=327) and 10 host European (n=849) non-Jewish populations. Only four mtDNA haplogroups (Hgs) (defined on the basis of diagnostic coding region RFLPs and HVS-1 sequence variants) account for approximately 70% of Ashkenazi mtDNA variation. While several Ashkenazi Jewish mtDNA Hgs appear to derive from the Near East, there is also evidence for a low level of introgression from host European non-Jewish populations. HVS-1 sequence analysis revealed increased frequencies of Ashkenazi Jewish haplotypes that are rare or absent in other populations, and a reduced number of singletons in the Ashkenazi Jewish sample. These diversity patterns provide evidence for a prolonged period of low effective size in the history of the Ashkenazi population. The data best fit a model of an early bottleneck (approximately 100 generations ago), perhaps corresponding to initial migrations of ancestral Ashkenazim in the Near East or to Europe. A genetic bottleneck followed by the recent phenomenon of rapid population growth are likely to have produced the conditions that led to the high frequency of many genetic disease alleles in the Ashkenazi population.
authors.affiliation: Bruce Rappaport Faculty of Medicine and Research Institute, Technion and Rambam Medical Center, Haifa, Israel.
authors.forename: Doron M
authors.initials: DM
authors.lastname: Behar
authors.forename: Michael F
authors.initials: MF
authors.lastname: Hammer
authors.forename: Daniel
authors.initials: D
authors.lastname: Garrigan
authors.forename: Richard
authors.initials: R
authors.lastname: Villems
authors.forename: Batsheva
authors.initials: B
authors.lastname: Bonne-Tamir
authors.forename: Martin
authors.initials: M
authors.lastname: Richards
authors.forename: David
authors.initials: D
authors.lastname: Gurwitz
authors.forename: Dror
authors.initials: D
authors.lastname: Rosengarten
authors.forename: Matthew
authors.initials: M
authors.lastname: Kaplan
authors.forename: Sergio
authors.initials: S
authors.lastname: Della Pergola
authors.forename: Lluis
authors.initials: L
authors.lastname: Quintana-Murci
authors.forename: Karl
authors.initials: K
authors.lastname: Skorecki
mesh_terms: D004252:DNA Mutational Analysis; D004272:DNA, Mitochondrial / Q000737:chemistry / Q000235:genetics*; D005787:Gene Frequency; D014644:Genetic Variation; D005828:Genetics, Population; D005838:Genotype; D006239:Haplotypes / Q000235:genetics*; D006801:Humans; D007585:Jews / Q000235:genetics*; D008957:Models, Genetic; D009154:Mutation
chemical_list: D004272:DNA, Mitochondrial