New data on the genetic structure of the population of Sicily: analysis of the Alia population (Palermo, Italy).

The distribution of 13 genetic markers (AB0, Rh, ACP, ADA, AK, ESD, GLO, PGD, PGMl, SOD, GC, TF, and PI) were studied in a sample from the Alia population of Sicily, Italy. A total of 34 alleles were detected. In comparison with other Sicilian populations, Alia always appeared genetically distinctive, either in terms of overall genetic diversity or for the number of unique alleles present. The results are consistent with previous studies that show no genetic uniformity within the island. More specifically, the data support the genetic divergence of the eastern and western halves of the island and highlight genetic boundaries that run through Sicily and divide it into three distinct areas.

Mitochondrial control-region sequence variation in the Corsican population, France.

The mtDNA sequence variation of the hypervariable segment I of the control region was studied in 47 unrelated individuals of Corsican origin from Corte (Corsica, France). Thirty-one different sequences were identified by 40 variable sites, of which five involve transversions. The nucleotide diversity among the sequences was estimated as 1.03%. The pairwise difference agreed with the model proposed by Rogers and Harpending ([1992] Mol Biol Evol 9:552-569) and appeared bell-shaped, with only one peak at 3.71, indicating the occurrence of a single episode of demographic expansion roughly 14,443 to 41,584 years ago. From our results it seems that the ancestral Corsican population expanded more recently than all other studied European populations. Compared to other populations by genetic distances and a neighbor-joining tree, Corsicans appear most closely linked to the Basques and Sardinians than to other populations. Although the results substantiate an east-to-west migration, some problems are evident: 1) the estimates of demographic expansion are not in agreement with paleontological data; 2) the expansion occurred later than the expansion of the Sardinian population; and 3) the genetic affinity between Corsicans, Basques, and Sardinians. Answers will need to come from archaeological, paleontological, genetic, geological, and climatological observations. Finally, the study of mtDNA confirms what had already been shown with classic genetic markers. Am. J. Hum. Biol. 12:339-351, 2000. Copyright 2000 Wiley-Liss, Inc.

Red cell enzyme polymorphisms in Moroccans and southern Spaniards: new data for the genetic history of the western Mediterranean.

Population samples from Morocco (El Jadida, south Atlantic coast) and La Alpujarra (Granada mountains, Spain), located on both shores of the western Mediterranean, were typed for 8 erythrocyte genetic markers: ACP1, ESD, PGD, AK1, GLO1, PGM1, SODA, and DIA. Genetic heterogeneity within western Mediterranean groups was investigated on the basis of allele frequencies of these 8 polymorphisms plus ABO and Rh (CDE). Only slight peculiarities for the ACP1, GLO1, and AK1 systems were observed in the 2 samples compared with other Mediterranean data. The new data are consistent with a main north to south genetic differentiation in the Mediterranean region. However, with regard to other European groups, the La Alpujarra population shows a particular affinity with North Africans that may be compatible with both an ancient common substratum and/or a special historical influence during the Muslim domination of the Iberian Peninsula.

The polymorphism of the APOB 3' VNTR in the populations of the three largest islands of the western Mediterranean.

To enlarge the knowledge of genetic characteristics of the populations of the three largest islands of the Western Mediterranean--Corsica (France), Sardinia and Sicily (Italy)--the allele distribution of the VNTR APOB 3' locus was studied. A total of 250 individuals was examined. Twelve different alleles were found, with a minimum of 7 alleles in Sicily and a maximum of 9 alleles in the Sardinians from Campidano of Cagliari and Nuorese. The most frequent allele in all the samples is allele 37, followed by allele 35. The allele frequency distribution appears to be bimodal and the expected heterozygosity is not much higher in comparison with other populations. The polymorphic Information Content (PIC) has a value of 0.84. The Fisher exact test, the matrix of the distances and the dendrogram drawn up from it show a certain heterogeneity between the populations of the three islands, a great variability within Sardinia and a certain degree of affinity between Corsica and the north of Sardinia.

Genetic structure of southwestern Corsica (France).

The distribution of nine red cell enzymes (ACP, ADA, AK, DIA, ESD, GLO1, PGM1, PGD, and SOD) and seven plasma proteins (C3, GC, HP, ORM, PI, PLG, and TF) was analyzed in a sample of 274 unrelated individuals from the southwestern area of Corsica (France), specifically from Ajaccio and nearby villages. The aim of the research was to study the genetic structure of Corsica and to add further to our knowledge about microgeographic variability of polymorphisms in Corsica. The analysis, carried out by genetic distances and R-matrix through 39 alleles of 13 genetic markers, reveals a certain degree of differentiation within Corsica. The results show a genetic heterogeneity between Corsica and other European and Mediterranean populations, although the genetic differences appear to be smaller between Corsicans and Sardinians than among Corsicans and other compiled populations. Am. J. Hum. Biol. 10:567-577, 1998. © 1998 Wiley-Liss, Inc.

HLA phenotype and haplotype frequencies in Sardinia (Italy).

The gene and haplotype frequencies of the HLA-A, B, Cw, DR and DQ loci were determined in two Sardinian samples from the Nuoro (N = 252) and Sassari (N = 153) districts. Our data were compared with those reported for other Italian, European and Mediterranean populations and previously studied Sardinian samples. The results showed that the two samples differ from other Italian and European populations in the frequencies of many alleles and haplotypes. For example in the A2, B18, Cw5 and DR3 allele frequencies and the A1-B8, A2-B17, A3-B7, A30-B18, A2-Cw7, A30-Cw5, A30-DR3, A32-DR2, Cw5-DR3 and Cw7-DR4 haplotype frequencies. In common with the Mediterranean populations, Sardinians, too, have a limited number of haplotypes with significant linkage disequilibrium. The results revealed, therefore, significant genetic differentiation between Sardinians and other European and Mediterranean populations, confirming the genetic peculiarity of the Sardinians.

Genetics, geography, and culture: the population of S. Pietro Island (Sardinia, Italy).

An interesting aspect of the island of Sardinia (Italy) is the wide range of genetic variability within the island itself. The variability is widened by the presence of some populations of different ethnic origin who speak a language other than Sardinian. This work deals with the study of the genetic structure of the Carloforte population which inhabits the tiny island of S. Pietro 4 km off the southwest coast of Sardinia. S. Pietro was first populated in 1738 by emigrants coming from the island of Tabarka (Tunisia) who spoke an archaic form of the Ligurian dialect. Data on genetic polymorphisms in the Carloforte population are presented and discussed in relation to some Sardinian and Italian populations. Data on demographic and matrimonial structure are also presented. The genetic analyses show the Carloforte population as being clearly separated from both Sardinians and continental Italians. The isolation of Carloforte, highlighted by language diversity, endogamy, and consanguinity levels and marriage area, supports the idea of genetic diversity linked to cultural peculiarity.

Study on the variability of seven genetic serum protein markers in Corsica (France).

By this investigation we want to contribute to our knowledge on the genetic characteristics of the Corsican population. The distribution of seven genetic serum protein markers (PI, TF, GC, ORM, HP, C3, PLG) was analyzed in a sample of 291 individuals coming from the central and northern areas of Corsica, i.e. from Corte and Bastia. The two samples do not show significant differences in the distribution of the genetic markers under study. The comparisons with other Mediterranean populations confirm the results of previous investigations on genetic red cell enzyme markers (Vona et al. 1995), i.e. a relatively high genetic heterogeneity of Corsicans compared with other Mediterranean populations.

Variability of the CD4 and F13A1 short tandem repeats in Corsicans, Sardinians and Piaroa Indians.

This paper presents allele frequencies of two short tandem repeats (CD4 and F13A1) in three anthropologically defined populations: Sardinians (Italy), Corsicans (France) and Piaroa Indians (Venezuela). The comparison shows some relevant differences both in number and distribution of the CD4 and F13A1 alleles.

Genetic analysis of Sardinia: I. data on 12 polymorphisms in 21 linguistic domains.

(1) The microgeographic structure of Sardinia, well documented from a historical and linguistic point of view, further supported by archaeological evidence, can also be dissected at the genetic level: gene frequencies show heterogeneities which are statistically significant. (2) Dendrogram analyses performed with different methods lead to the same result: even if gene frequencies cluster linguistically defined geographic domains in agreement with historical and archaeological evidence, no phylogenetic tree can be inferred, very likely because the assumptions which allow a phylogenetic tree to be a valid model of evolution (mainly constant evolutionary rates and independence between branches) do not apply to the genetic history of Sardinia. (3) Evidence of a qualitative association between distribution of genes and distribution of languages or dialects seems to emerge also at the microgeographic level of our analysis. More linguistic and genetic data are planned to be considered.

A study of several genetic markers in the Corsican population (France).

The distribution of nine genetic markers was studied in a sample of 170 individuals coming from Corte (Corsica, France). The corresponding gene frequencies were as follows: ACP*A = 0.080, ACP*B = 0.887, ACP*C = 0.033; ESD*1 = 0.854; AK*1 = 0.976; PGD*A = 0.991; DIA*1 = 0.994; GLO1*1 = 0.278; PGM1*1S = 0.694, PGM1*1F = 0.100, PGM1*2S = 0.153, PGM182F = -.053; C3*S = 0.793, C3*F = 0.183, C3*V = 0.024; GC*1S = 0.713, GC*1F = 0.079; GC*2 = 0.207. These findings were discussed in the context of other Mediterranean populations. The results showed a relatively high genetic heterogeneity of Corsicans compared to other populations. The genetic differences appeared to be smaller between Corsicans and Sardinians than among Corsicans and other Mediterraneans.

Distribution of PGM1 and GC subtypes in the four Sardinian provinces.

Genetic polymorphism subtypes of PGM1 and GC were studied in four samples of the Sardinian population from the four Provinces of the island. The results show heterogeneity within the Sardinian population. The PGM1 alleles exhibiting the greatest variability were: PGM1*1S and PGM1*1F, with a range of .675-.724 (Nuoro - Sassari) and .072-.107 (Sassari - Nuoro) respectively. The observed GC allele frequency range were: GC*1F = .029-.168 (Cagliari - Sassari); GC*1S = .565-.752 (Sassari - Oristano); GC*2 = .194-.267 (Cagliari - Sassari). Sardinians showed a marked differentiation with respect to other Italian and European populations thus confirming their genetic peculiarity.

C3 polymorphism and NADH diaphorase types in Sardinia (Italy).

C3 and DIA1 types were studied in Sardinians from four provinces. C3 showed a heterogeneous distribution in the four subsamples and C3*F gene varied between 0.235 (Province of Sassari) and 0.154 (Province of Oristano). No rare types were found in Sardinia in contrast to mainland Italy. There are significant differences compared with some Italian populations on the mainland. DIA1*2 allele varies between 0.0026 (Province of Cagliari) and 0.0157 (Province of Nuoro). Also DIA1 showed a heterogenous distribution.

Gc and C3 polymorphisms in South Sardinia.

The distribution of phenotypes and gene frequencies of the group-specific component (Gc) and C3 complement were studied in South Sardinia. The gene frequencies were: Gc1 = 0.7346; C3F = 0.1963.

AcP and EsD polymorphisms in South Sardinia.

A sample of the South Sardinia population was studied with respect to acid phosphatase (AcP) and esterase D (EsD) enzymes. The gene frequencies were: AcPA = 0.326, AcPB = 0.607, AcPC = 0.067 and EsD1 = 0.883. The results were compared with those of other Italian populations.

AK and ADA polymorphisms in South Sardinia.

A sample of the South Sardinia population was studied with respect to adenylate kinase (AK) and adenosine deaminase (ADA) enzymes. The gene frequencies were: AK1 0.975 and ADA1 = 0.933. The results were compared with those of other Italian populations.

6PGD and PGM1 polymorphisms in south Sardinia.

A sample of unrelated individuals, born and living in South Sardinia, was studied with respect to the enzymes 6PGD and PGM1. The gene frequencies were: PGDA 0.989 and PGM1 0.790. The results were compared with those of other Italian populations.