Small effective population size and genetic homogeneity in the Val Borbera isolate.
Population isolates are a valuable resource for medical genetics because of their reduced genetic, phenotypic and environmental heterogeneity. Further, extended linkage disequilibrium (LD) allows accurate haplotyping and imputation. In this study, we use nuclear and mitochondrial DNA data to determine to what extent the geographically isolated population of the Val Borbera valley also presents features of genetic isolation. We performed a comparative analysis of population structure and estimated effective population size exploiting LD data. We also evaluated haplotype sharing through the analysis of segments of autozygosity. Our findings reveal that the valley has features characteristic of a genetic isolate, including reduced genetic heterogeneity and reduced effective population size. We show that this population has been subject to prolonged genetic drift and thus we expect many variants that are rare in the general population to reach significant frequency values in the valley, making this population suitable for the identification of rare variants underlying complex traits.
Institute of Genetics and Biophysics 'A. Buzzati-Traverso', National Research Council (CNR), Naples, Italy. vincenza.colonna@igb.cnr.it
Vincenza
V
Colonna
Giorgio
G
Pistis
Lorenzo
L
Bomba
Stefano
S
Mona
Giuseppe
G
Matullo
Rosa
R
Boano
Cinzia
C
Sala
Fiammetta
F
Viganò
Antonio
A
Torroni
Alessandro
A
Achilli
Baharak
B
Hooshiar Kashani
Giovanni
G
Malerba
Giovanni
G
Gambaro
Nicole
N
Soranzo
Daniela
D
Toniolo
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016000:Cluster Analysis; D004272:DNA, Mitochondrial; D040961:Genetic Drift; D014644:Genetic Variation; D005828:Genetics, Population; D006239:Haplotypes; D006720:Homozygote; D006801:Humans; D007558:Italy; D015810:Linkage Disequilibrium; D008875:Middle Aged; D008957:Models, Genetic; D010375:Pedigree; D011156:Population Density; D055815:Young Adult
D004272:DNA, Mitochondrial