title: Genotyping of geographically diverse Druze trios reveals substructure and a recent bottleneck.
abstract: Druze individuals rarely marry outside their faith (often practicing consanguinity) and are thus believed to form a genetic isolate. To comprehensively characterize the genetic structure of the Druze population, we recruited and genotyped 40 parent-offspring trios from the Upper Galilee in Israel and the Golan Heights, attempting to capture different extended families (clans) across various geographical locations. Principal component (PC) and ADMIXTURE analyses demonstrated that Druze are close to, yet distinct from, other Middle-Eastern groups (Bedouins and Palestinians), supporting the Druze's Middle-Eastern origin and their recent genetic isolation. Reconstruction of the Druze demographic history using identical-by-descent (IBD) segments suggested an ≈15-fold reduction in population size taking place ≈22-47 generations ago, close to the documented time of the foundation of the Druze faith at the 11th century. Combining the Galilee and Golan Druze genotypes with previously published data on Druze from the Carmel (Israel) and Lebanon demonstrated that all four Druze communities are genetically distinct. The Lebanese group shared less IBD segments (within the group and with other groups) compared with the Israeli Druze and showed higher heterozygosity (suggesting less consanguinity), but was less diverse in PC space. These findings suggest complex recent and ancient demographic history of the Druze population.
authors.affiliation: The Oncology Department, Ziv Medical Center, The Faculty of Medicine in the Galilee, Bar-Ilan University, Zefat, Israel.
authors.forename: Jamal
authors.initials: J
authors.lastname: Zidan
authors.affiliation: Department of Medicine and Genetics, Albert Einstein College of Medicine, Bronx, NY, USA.
authors.forename: Dan
authors.initials: D
authors.lastname: Ben-Avraham
authors.affiliation: Department of Computer Science, Columbia University, New York, NY, USA.
authors.forename: Shai
authors.initials: S
authors.lastname: Carmi
authors.affiliation: Golan for Development, Madjal Shams, The Golan Heights, Israel.
authors.forename: Taiseer
authors.initials: T
authors.lastname: Maray
authors.affiliation: 1] The Susanne Levy Gertner Oncogenetics Unit, The Danek Gertner Institute of Human Genetics, Chaim Sheba Medical Center, Tel-Hashomer, Israel [2] The Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Eitan
authors.initials: E
authors.lastname: Friedman
authors.affiliation: Department of Medicine and Genetics, Albert Einstein College of Medicine, Bronx, NY, USA.
authors.forename: Gil
authors.initials: G
authors.lastname: Atzmon
mesh_terms: D018912:Arabs / Q000235:genetics*; D005006:Ethnicity / Q000235:genetics*; D005838:Genotype; D006801:Humans; D007557:Israel; D007861:Lebanon