Genetic differentiation among Sardinian villages

Abstract

The present study reports an analysis of genetic differentiation among 14 Sardinian villages located mainly in the center of the island. Chi-square tests show significant genetic heterogeneity among villages, and analyses by F- and R- statistics indicate an essentially random pattern of differentiation for all alleles. Using the kinship methods of Morton, a matrix, R, with elements rij describing the correlations between the gene frequencies of villages i and j is obtained. Use of Malécot's formula relating the rij to the geographic distances between villages shows a rapid decline of kinship with increasing distance but reveals essentially no relationship for distances over 40 km. Rotation of a two-dimensional reduction of the kinship matrix to maximum congruence with the geographic distances indicates that about 25% of the genetic distances can be accounted for by the geographic location of the villages. Isolation due in part to cultural factors, genetic drift, and special local or regional patterns of villages associations appear to be involved in the pattern of genetic variation.

AcP and EsD Polymorphisms in Central Sardinia

“…There were significant differences between our sample and many other Italian populations and previously studied Sardinian samples [4,5]. The EsD1 allele in our sample showed a low frequency but was in line with other Italian samples (range: 0.837-0.950) [3].…”

3000 years of solitude: extreme differentiation in the island isolates of Dalmatia, Croatia

“…Similar situations of differentiation within short distances, have been reported among villages geographically no more than 15 -25 km apart in the mountainous Bosnian area, 7 and have long been recognised in Sardinia. 32 The organization into small groups (substructuring) was probably a characteristic demographic feature during the vast majority of human population history, and persists today to a greater or lesser degree in many rural areas. This phenomenon is largely ignored when modelling human population history and may lead to distorted demographic inferences.…”

Review Synthetic Article: Sardinian Population (Italy): a Genetic Review

“…The studies on internal genetic diversity suggest a fragmentation of the Sardinian population into numerous isolates. The differences emerging within the island have been attributed by most authors to genetic drift, which would be strongly active because of the natural boundaries (Workman et al, 1975). Terrenato et al (1971) recognize in each Sardinian village a genetic isolate.…”