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Allele frequencies of 17 Y-chromosome short tandem repeat (STR) loci, included in the AmpFlSTR® Y-FilerTM amplification kit, were analyzed for the first time in different samplings (N=268) from Sardinia, Italy. Samples were collected from three isolated populations (N=139) and three open populations (N=129). A total of 230 unique haplotypes were detected; the observed haplotype diversity and discrimination capacity were 0.998 and 0.858, respectively. The data presented confirm that Sardinian population is well differentiated from other Italian and Mediterranean populations. Although regarded as a homogeneous population, substantial heterogeneity was detected when Sardinian isolated villages or microareas were analyzed. Our results highlights the importance of building a Sardinia-own database, organized by small areas, as a powerful tool for both forensic applications and population genetics studies., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Objectives: The aims of this work are to provide first data on novel STRs at the NOS gene regions in human populations and to test for possible correlations with mortality rate by malaria in different areas of Sardinia (Italy)., Methods: In the present study, 16 STRs (13 analyzed for the first time in human populations) localized on three genes NOS were typed in 213 healthy individuals, unrelated for at least three generations, from six historical-geographical Sardinian areas. STRs alleles were determined through sequencing. Statistical analyses were performed by Genepop (v.4.0), Arlequin (v.3.5.1.2), R (v.2.15.1), Statistica (v.5.1), and PHASE (v.2.1) software packages., Results: The number of alleles found for each locus ranged from 2 to 12 and their distribution is most often unimodal. All populations met Hardy Weinberg equilibrium after Bonferroni correction, with few exceptions. Analysis of genetic distances did not show strong genetic structuring of the investigated populations. Instead, the population genetic variability shows a positive and highly significant (P-value < 0.01) correlation between mortality determined by malaria infection and alleles (TGGA)7 of NOS2, (AAAAG)2 and (ATTT)10 of adNOS1, and (AAACA)11 of adNOS3 genes., Conclusions: The peculiar allele distribution found for several NOS alleles could be due to malaria infection that may have contributed to their frequencies, but we cannot exclude that the peculiar allele distribution of NOS might also be due to genetic drift, emphasized by isolation and founder effect., (Copyright © 2014 Wiley Periodicals, Inc.)

The animal and plant biodiversity of the Italian territory is known to be one of the richest in the Mediterranean basin and Europe as a whole, but does the genetic diversity of extant human populations show a comparable pattern? According to a number of studies, the genetic structure of Italian populations retains the signatures of complex peopling processes which took place from the Paleolithic to modern era. Although the observed patterns highlight a remarkable degree of genetic heterogeneity, they do not, however, take into account an important source of variation. In fact, Italy is home to numerous ethnolinguistic minorities which have yet to be studied systematically. Due to their difference in geographical origin and demographic history, such groups not only signal the cultural and social diversity of our country, but they are also potential contributors to its bio-anthropological heterogeneity. To fill this gap, research groups from four Italian Universities (Bologna, Cagliari, Pisa and Roma Sapienza) started a collaborative study in 2007, which was funded by the Italian Ministry of Education, University and Research and received partial support by the Istituto Italiano di Antropologia. In this paper, we present an account of the results obtained in the course of this initiative. Four case-studies relative to linguistic minorities from the Eastern Alps, Sardinia, Apennines and Southern Italy are first described and discussed, focusing on their micro-evolutionary and anthropological implications. Thereafter, we present the results of a systematic analysis of the relations between linguistic, geographic and genetic isolation. Integrating the data obtained in the course of the long-term study with literature and unpublished results on Italian populations, we show that a combination of linguistic and geographic factors is probably responsible for the presence of the most robust signatures of genetic isolation. Finally, we evaluate the magnitude of the diversity of Italian populations in the European context. The human genetic diversity of our country was found to be greater than observed throughout the continent at short (0-200 km) and intermediate (700-800km) distances, and accounted for most of the highest values of genetic distances observed at all geographic ranges. Interestingly, an important contribution to this pattern comes from the "linguistic islands"( e.g. German speaking groups of Sappada and Luserna from the Eastern Italian Alps), further proof of the importance of considering social and cultural factors when studying human genetic variation.

We reviewed data collected during several studies concerning the genetic isolate of Carloforte (Sardinia, Italy) and analyzed new data on Y-chromosome markers. Carloforte is also a language island, where people still speak Tabarchino, an archaic form of Ligurian dialect. Demographic data indicate that, in the early years of its history, the Carloforte population was characterized by a high degree of endogamy and consanguinity rates that started to decrease around 1850, when marriages with Sardinian people began to occur more frequently. Cultural factors, mainly language, account for the high endogamy. Genetic data from classical markers, mtDNA, and Y-chromosome markers confirmed the strong isolation of the Carloforte population, which appears significantly different from the neighboring population of Sardinia. Analysis of mtDNA emphasizes the crucial aspect of sampling strategy-two different samplings of the same population (one based on founder surnames; the other based on grandparents' criterion) gave different results. Founder surnames sampling is not affected by recent events, and therefore it better describes the ancestral population, whereas, grandparents' criterion sampling gives a picture of the present population, shaped by more recent events, such as migration and gene flow. This review further supports the notion that a comprehensive approach, including a detailed knowledge of the history of the population and the collection of different samplings, is essential in anthropology for reconstructing past and recent events that contributed to establishing the present genetic structure of the population. Likewise, it is essential in medical genetics to identify genes involved in complex diseases. An ideal scenario is offered by a genetic isolate with a recent, and well-documented, history, such as Carloforte, that can ba a paradigm for this type of investigation., (Copyright © 2013 Wayne State University Press, Detroit, Michigan 48201-1309.)

This paper explores the genetic structure and signatures of natural selection in different sub-populations from the Island of Sardinia, exploiting information from nearly 700,000 autosomal SNPs genotyped with the Affymetrix Genome-Wide Human SNP 6.0 Array. The genetic structure of the Sardinian population and its position within the context of other Mediterranean and European human groups were investigated in depth by comparing our data with publicly available data sets. Principal components and admixture analyses suggest a clustering of the examined samples in two significantly differentiated sub-populations (Ogliastra and Southern Sardinia), as confirmed by AMOVA (F(ST)=0.011; P<0.001). Differentiation of these sub-populations was still evident when they were pooled together with supplementary Sardinian samples from HGDP and compared with several other European, North-African and Near Eastern populations, confirming the uniqueness of the Sardinian genetic background. Moreover, by applying several statistical approaches aimed at assessing differences at the SNP level, the highest differentiated genomic regions between Ogliastra and Southern Sardinia were thus investigated via an extended haplotype homozygosity (EHH)-based test to point out potential selective sweeps. Using this approach, 40 genomic regions were detected, with significant differences between Ogliastra and Southern Sardinia. These regions were subsequently investigated using a long-range haplotype test, which found significant REHH values for SNPs rs11070188 and rs11070192 in the Ogliastra sub-population. In the light of these results and the overlap of the different computed statistics, the region encompassing these loci can be considered a strong candidate to have undergone selective pressure in Ogliastra.

Aim: The aim of the present paper was to investigate the relationships between polymorphisms in ACTN3, ACE and BDKRB2 genes, soccer performance, and explosive leg-muscle strength in Italian soccer players., Methods: We examined 42 top-level Italian soccer players (S) and 106 sedentary healthy Italians, as a control group (C). χ2 test was used to look for the difference in genotype distribution of ACTN3, ACE and BDKRB2 between groups. The data were evaluated by forward stepwise multiple regression analysis with the Squat Jump (SJ) and Counter Movement Jump (CMJ) as dependent variables, as well as competition level (CL), ACTN-3, ACE and BDKRB2 genotypes as independent variables., Results: No significant difference was found between groups for ACE, ACTN-3 and BDKRB2 genotype distributions. Forward stepwise multiple regression analysis suggests a significant relationship between a) SJ vs. CL, ACE, and ACTN-3 and b) CMJ vs. CL. For SJ, the multivariate model combining genotypic data and competition level significantly predicted explosive leg-muscle strength in soccer players and variance explained by the function was 23.92%., Conclusion: An interaction of two polymorphisms (ACE and ACTN-3) might be able to discriminate quantitative traits crucial for the elite soccer performance, however the contribution of genetic factors to soccer performance is not so high.

Objectives: Sampling strategies are crucial issues in population genetics and anthropological studies. The sampling choice is related to the research question and the type of markers used. In this research, we compared two different sampling strategies in the Sardinian linguistic isolate of Carloforte (Italy)., Methods: A first sampling (N = 49) was carried out through grandparents criterion: individuals selected for the study were born and resident in Carloforte, and unrelated for at least three generations. A second sampling (N = 50) was based on founders surnames (FS): selected participants were proved to be descendants of the village founders, and to have no ancestors in common, at least up to the grandparental generation., Results: The group selected through FS showed a greater gene diversity, which was confirmed by both network and haplogroup analysis. Among the shared haplogroups, we find clear differences in their frequencies. Sampling through grandparents criterion showed essentially the same haplogroups found in Sardinia, and with similar frequencies. Interesting results came from genetic tree. The FS sampling clustered with Northern African populations and it is located very far from Italian and Sardinian populations, whereas the grandparents criterion sampling clustered with Italian populations and it is located close to the other Sardinian populations., Conclusions: Results showed that different sampling strategies can lead to contrasting results. As sampling through grandparents criterion is influenced by recent gene flow, we hypothesize that the difference observed with the two sampling strategies is due to the merging of Carloforte with Sardinian populations., (Copyright © 2012 Wiley Periodicals, Inc.)

The PROP taste phenotype varies greatly among individuals, influencing eating behavior and therefore may play a role in body composition. This variation is associated with polymorphisms in the bitter receptor gene TAS2R38 and the taste-bud trophic factor gustin gene. The aim of this study was to examine the relationship between TAS2R38 haplotypes and the gustin gene polymorphism rs2274333 in modulating PROP taste phenotype. PROP phenotype was determined in seventy-six volunteers (29 males, 47 females, age 25±3 y) by scaling methods and threshold measurements. TAS2R38 and gustin gene genotyping was performed using PCR techniques. The lowest responsiveness in PROP nontasters is strongly associated with the AVI nontasting TAS2R38 variant and the highest responsiveness in supertasters is strongly associated to allele A and genotype AA of the gustin gene. These data support the hypothesis that the greater sensitivity of supertasters could be mediated by a greater taste-bud density. Polymorphisms in TAS2R38 and gustin gene, together, accounted for up to 60% of the phenotypic variance in PROP bitterness and to 40% in threshold values. These data, suggest that other unidentified factors may be more relevant for detecting low concentrations of PROP. Moreover, the presence of the PAV variant receptor may be important for detecting high concentrations of PROP, whereas the presence of allele A in gustin polymorphism may be relevant for perceiving low concentrations. These data show how the combination of the TAS2R38 and gustin gene genotypes modulate PROP phenotype, providing an additional tool for the evaluation of human eating behavior and nutritional status., (Copyright © 2011 Elsevier Inc. All rights reserved.)