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Isolation is a known force in evolutionary biology and one of the main factors in speciation. One of the main consequences of severe isolation is reduced mate choice, which results in the occurrence of inbreeding as a result of isolation. We investigated the effects of individual genome-wide heterozygosity measured as the multilocus heterozygosity (MLH) on biochemical markers of hemostasis and inflammation in 1,041 individuals from the island of Vis, Croatia, where inbreeding is prevalent and a wide range of variation in the genome-wide heterozygosity is expected. Assessment of individual genome-wide heterozygosity was based on genome-wide scans using 800 microsatellite (STR) and 317,503 single nucleotide (SNP) polymorphic markers in each examinee. In addition, for each examinee we defined a personal genetic history (PGH) based on genealogical records. The association between PGH and MLH and fibrinogen, D-dimer (Dd), von Willebrand factor (vWF), tissue plasminogen activator (tPA), and C-reactive protein (CRP) was performed with a mixed model, controlling for possible confounding effects. PGH was a significant predictor only for tPA (P < 0.001), whereas neither of the two MLH measures exhibited significant association with any of the investigated traits. The effects of individual genome-wide heterozygosity are most likely expressed in highly polygenically determined traits or in traits that are mediated by rare and recessive genetic variants. Weak associations between PGH and MLH and markers of hemostasis and inflammation suggest that their genetic control may not be highly polygenic and that they could be promising targets for genetic association studies.

Background: The French has been insufficiently characterized so far for mitochondrial DNA (mtDNA) diversity., Aims: The study aimed to enhance the information available for the French mtDNA pool and to explore the potential microgeographical differentiation of two French regions selected for their linguistic and historical idiosyncrasies., Subjects and Methods: A total of 868 samples from 12 different locations in France were collected. They were sequenced for the hypervariable segment I (HVS-I) and typed for haplogroup defining markers from the coding region either by restriction fragment length polymorphism (RFLP) or by a new protocol based on the 5' nuclease allelic discrimination. The mtDNA gene pools of French Basques and Bretons were compared in terms of frequency and composition with relevant neighbouring populations., Results: The French Basques' mtDNA pool shares some common features with that of the Spanish Basques, such as the high frequency of haplogroup H. However, the French Basques exhibit a number of distinct features, most notably expressed in the prevalence of haplogroups linked with the Neolithic diffusion in Europe. In Brittany, Finistère shows closer affinities with Britain and Scandinavia than the two other departments of Brittany., Conclusion: The mtDNA haplogroup composition of the French does not differ significantly from the surrounding European genetic landscape. At a finer grain, microgeographical differentiation can be revealed, as shown for the French Basque country and for Brittany.

Eight Y-STR polymorphisms (DYS19, DYS385, DYS389I, DYS389II, DYS390, DYS391, DYS392 and DYS393) were analyzed in the samples of 181 unrelated males from Bosnia and Herzegovinia. Observed STR allelic frequency pattern and locus diversity values in Bosnians and Herzegovinians correspond closer to neighboring southeastern European populations than previously reported (mostly western) European populations. One hundred and five haplotypes were identified and 78 haplotypes (74.3%) appeared in single copies. The most frequent haplotypes (DYS19-DYS385-DYS389I-DYS389II-DYS390-DYS391-DYS392-DYS393) were 16-14/15-13-31-24-11-11-13 (7.7%), 16-14/15-13-30-24-11-11-13 (7.7%) and 15-14/15-13-31-24-11-11-13 (5.5%). Total haplotype diversity was 0.9820 +/- 0.0040.

Eight Y chromosome short tandem repeat (STR) polymorphisms (DYS19, DYS385, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393) were analyzed in Macedonians (n = 84) and Macedonian Romani ethnic group (n = 68). Observed allelic frequency distribution and locus diversity values in Macedonians correspond closer to neighboring southeastern European populations than (mostly) western European populations, whereas observed allelic frequency distribution and locus diversity values in Macedonian Romani, as expected based on their Asian (Indian) origin, differ from both neighboring southeastern and (mostly) western European populations. Sixty-six (78.57%) haplotypes appeared in single copies in Macedonians and 15 (22.06%) in Macedonian Romani. The most frequent Macedonian haplotypes (DYS19-DYS385-DYS389I-DYS389II-DYS390-DYS391-DYS392-DYS393) 16-14/15-13-31-24-11-11-13 and 13-16/18-13-30-24-10-11-13 were found in 7 and 6 copies, respectively. The most frequent Macedonian Romani haplotype 15-15/17-14-29-22-10-11-12 was found in 18 males. Total haplotype diversity was 0.9885 +/- 0.0058 (Macedonians) and 0.9008 +/- 0.0242 (Macedonian Romani).

The extent and nature of southeastern Europe (SEE) paternal genetic contribution to the European genetic landscape were explored based on a high-resolution Y chromosome analysis involving 681 males from seven populations in the region. Paternal lineages present in SEE were compared with previously published data from 81 western Eurasian populations and 5,017 Y chromosome samples. The finding that five major haplogroups (E3b1, I1b* (xM26), J2, R1a, and R1b) comprise more than 70% of SEE total genetic variation is consistent with the typical European Y chromosome gene pool. However, distribution of major Y chromosomal lineages and estimated expansion signals clarify the specific role of this region in structuring of European, and particularly Slavic, paternal genetic heritage. Contemporary Slavic paternal gene pool, mostly characterized by the predominance of R1a and I1b* (xM26) and scarcity of E3b1 lineages, is a result of two major prehistoric gene flows with opposite directions: the post-Last Glacial Maximum R1a expansion from east to west, the Younger Dryas-Holocene I1b* (xM26) diffusion out of SEE in addition to subsequent R1a and I1b* (xM26) putative gene flows between eastern Europe and SEE, and a rather weak extent of E3b1 diffusion toward regions nowadays occupied by Slavic-speaking populations.

The aim of this review is to summarize the existing data collected in high-resolution phylogenetic studies of mitochondrial DNA and Y chromosome variation in mainland and insular Croatian populations. Mitochondrial DNA polymorphisms were explored in 721 individuals by sequencing mtDNA HVS-1 region and screening a selection of 24 restriction fragment length polymorphisms (RFLPs), diagnostic for main Eurasian mtDNA haplogroups. Whereas Y chromosome variation was analyzed in 451 men by using 19 single nucleotide polymorphism (SNP)/indel and 8 short tandem repeat (STR) loci. The phylogeography of mtDNA and Y chromosome variants of Croatians can be adequately explained within typical European maternal and paternal genetic landscape, with the exception of mtDNA haplogroup F and Y-chromosomal haplogroup P* which indicate a connection to Asian populations. Similar to other European and Near Eastern populations, the most frequent mtDNA haplogroups in Croatians were H (41.1%), U5 (10.3%), and J (9.7%). The most frequent Y chromosomal haplogroups in Croatians, I-P37 (41.7%) and R1a-SRY1532 (25%), as well as the observed structuring of Y chromosomal variance reveal a clearly evident Slavic component in the paternal gene pool of contemporary Croatian men. Even though each population and groups of populations are well characterized by maternal and paternal haplogroup distribution, it is important to keep in mind that linking phylogeography of various haplogroups with known historic and prehistoric scenarios should be cautiously performed.

This study examines the mitochondrial DNA (mtDNA) diversity of the Croatian-speaking minority of Molise and evaluates its potential genetic relatedness to the neighbouring Italian groups and the Croatian parental population. Intermatch, genetic distance, and admixture analyses highlighted the genetic similarity between the Croatians of Molise and the neighbouring Italian populations and demonstrated that the Croatian-Italian ethnic minority presents features lying between Croatians and Italians. This finding was confirmed by a phylogeographic approach, which revealed both the prevalence of Croatian and the penetrance of Italian maternal lineages in the Croatian community of Molise. These results suggest that there was no reproductive isolation between the two geographically proximate, yet culturally distinct populations living in Italy. The gene flow between the Croatian-Italians and the surrounding Italian populations indicate, therefore, that ethnic consciousness has not created reproductive barriers and that the Croatian-speaking minority of Molise does not represent a reproductively isolated entity.

We have analyzed the extent of genetic variation at nine autosomal short tandem repeat loci (D3S1358, VWA, FGA, TH01, TPOX, CSF1PO, D5S818, D13S317, D7S820) among six populations from Croatia: five distributed in the islands of the eastern Adriatic coast and one from the mainland. The purpose is to investigate the usefulness of these loci in detecting regional genetic differentiation in the studied populations. Significant heterogeneity among the island and mainland populations is revealed in the distributions of allele frequencies; however, the absolute magnitude of the coefficient of gene differentiation is small but significant. The summary measures of genetic variation, namely, heterozygosity, number of alleles, and allele size variance, do not indicate reduced genetic variation in the island populations compared to the mainland population. In contrast to the two measures of genetic variation, allele size variance and within-locus heterozygosity, the imbalance index (beta) indicates evidence of recent expansion of population sizes in all islands and in the mainland. High mutation rates of the studied loci together with local drift effects are likely explanations for interisland genetic variation and the observed lack of reduced genetic diversity among the island populations.

A complex segregation analysis of systolic and diastolic blood pressure has been performed on pedigree data from rural populations inhabiting Middle Dalmatian islands of Brac, Hvar and Korcula and the Peljesac peninsula. The purpose of the performed analysis was to possibly elucidate a signal of a large-effect gene responsible for high prevalence of hypertension present in this population (the age-adjusted prevalence of developed hypertension being 31.82% in males and 28.23% in females). The analysis was performed on a sample of 389 two- and three-generation families consisting of 2 to 19 observed individuals (1126 examinees in total, 526 males and 600 females, aged 17 to 83). Since the examinees were randomly selected from census data encompassing 22.6% of the total population--the family relations having been established afterwards--the selected sample can be considered representative for the examined populations. By applying the usual transmission probability tests, the major gene model has been accepted for systolic as well as for diastolic blood pressure. The most parsimonious models showed that: (a) inheritance of blood pressure in the Middle Dalmatia population can be attributed to the effect of a major gene responsible for 34% (systolic) and 36% (diastolic) blood pressure variation; (b) alleles of that major gene act in co-dominant fashion; (c) allele frequency for high blood pressure (A2) is 18% (systolic) and 15% (diastolic blood pressure); and (d) the residual (non-major gene) familial correlation is negligible and can be constrained to zero. Since the results are also indicating heterogeneity within the sample in the genetic determination of the systolic blood pressure, the obtained results thus justify further search for the most promising subpopulation for incoming genetic epidemiological investigations of hypertension.

Eight Y chromosome short tandem repeat (STR) polymorphisms (DYS19, DYS385, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393) were analyzed in the sample of 114 unrelated males living in Serbia. A general STR allelic frequency pattern in Serbians corresponds to other European populations with the exception of loci DYS19, DYS389II and DYS385. Out of ninety identified haplotypes, 74 (64.91%) appeared in single copies. The most frequent haplotypes (DYS19-DYS385-DYS389I-DYS389II-DYS390-DYS391-DYS392-DYS393) 16-14/15-13-31-24-11-11-13 and 15-15/19-12-28-23-10-12-12 were found in four copies (3.51%). Total haplotype diversity was 0.9947+/-0.0021.

The aim of this study was to investigate a recessive genetic component in susceptibility to osteoporosis (OP) by comparing its prevalence in isolated villages of three Croatian islands: Brac, Hvar and Korcula with different levels of inbreeding. A random sample of 20-30% adults from 14 villages was obtained, including a total of 1,389 examinees. The average inbreeding coefficient (F) of examinees from each village population was estimated using Wright's path method (based on genealogical information). The morphometry of the metacarpal bones was performed on hand-wrist radiographs of both hands in all examinees. OP was defined as values of cortical index smaller than 2 standard deviations based on distribution of values in examinees of the same sex under 45 years of age. Mean values of cortical index (CI) and prevalence of OP (both standardized by age and weighted for the sample size) in each village were correlated to the mean inbreeding coefficient (F). The coefficient of correlation (r) between F values and CI was -0.28 in males (p = 0.08) and -0.42 in females (p = 0.005), and between F and OP prevalence 0.32 in males (p < 0.001) and 0.43 in females (p < 0.001). These results indicate a trend of increased susceptibility to osteoporosis with increasing level of inbreeding in isolated communities of Croatian islands.

Alu elements are a family of interspersed repeats in the genome propagating by retroposition into new chromosomal locations. Alu insertion in Ace gene is known to be polymorphic (presence/absence of Alu element) in worldwide populations and as such serves as marker for population structure analyses. In this study we examined the distribution of genotypes and allele frequencies of this polymorphism in general Croatian population and its two isolates (the island of Hvar and the coastal region of the Middle Dalmatia) and related them to the level of endogamy as an indicator of inbreeding in these populations. Results showed that these three population groups are different with respect to Ace Alu polymorphism. The endogamy was highest on the island of Hvar. With the increase of endogamy a decrease in heterozigosity was observed. The same trend was observed for the frequency of insertion allele. Its frequencies in the village subpopulations of two studied isolates are subject to genetic drift due to small population sizes and high levels of endogamy. This in turn causes genetic differentiation among villages that is observed to be higher on the island of Hvar than in the coastal region. In the worldwide perspective, the Ace Alu insertion allele frequency of 50.6% in the general Croatian population falls within the range of other European populations.

Eight Y chromosome short tandem repeat (STR) polymorphisms (DYS19, DYS385, DYS389I, DYS389II, DYS390, DYS391, DYS392, and DYS393) were analyzed in the sample of 117 unrelated Albanian males living in Kosovo. A general STR allelic frequency pattern in the Albanian population from Kosovo corresponds to other European populations. Fourty six haplotypes were observed in single copy. The most frequent haplotypes were (DYS19-DYS385-DYS389I-DYS389II-DYS390-DYS391-DYS392-DYS393) 14-11/11-13-29-24-11-13-13 (10.26%), 14-14/17-12-28-24-10-11-12 (9.40%), 13-16/18-13-30-24-10-11-13 (9.40%), and 14-17/17-13-31-24-10-11-13 (9.40%).

To investigate which aspects of contemporary human Y-chromosome variation in Europe are characteristic of primary colonization, late-glacial expansions from refuge areas, Neolithic dispersals, or more recent events of gene flow, we have analyzed, in detail, haplogroup I (Hg I), the only major clade of the Y phylogeny that is widespread over Europe but virtually absent elsewhere. The analysis of 1,104 Hg I Y chromosomes, which were identified in the survey of 7,574 males from 60 population samples, revealed several subclades with distinct geographic distributions. Subclade I1a accounts for most of Hg I in Scandinavia, with a rapidly decreasing frequency toward both the East European Plain and the Atlantic fringe, but microsatellite diversity reveals that France could be the source region of the early spread of both I1a and the less common I1c. Also, I1b*, which extends from the eastern Adriatic to eastern Europe and declines noticeably toward the southern Balkans and abruptly toward the periphery of northern Italy, probably diffused after the Last Glacial Maximum from a homeland in eastern Europe or the Balkans. In contrast, I1b2 most likely arose in southern France/Iberia. Similarly to the other subclades, it underwent a postglacial expansion and marked the human colonization of Sardinia approximately 9,000 years ago.

Mitochondrial DNA polymorphisms were analyzed in of 1,610 randomly chosen adult men from 11 different regions from southeastern Europe (Croatians, Bosnians and Herzegovinians, Serbians, Macedonians and Macedonian Romani). MtDNA HVS-I region together with RFLP sites diagnostic for main Euroasian and African mtDNA haplogroups were typed to determine haplogroup frequency distribution. The most frequent haplogroup in studied populations was H with the exception of Macedonian Romani among whom the most frequent were South Asian (Indian) specific variants of haplogroup M. The multidimensional scaling plot showed two clusters of populations and two outliers (Macedonian Romani and the most distant from mainland Croatian island of Korcula). The first cluster was formed by populations from three Croatian islands (Hvar, Krk and Brac) and the second cluster was formed by Macedonians, Serbians, Croatians from mainland and coast, Herzegovinians, Bosnians, Slovenians, Poles and Russians. The present analysis does not address a precise evaluation of phylogenetic relations of studied populations although some conclusions about historical migrations could be noticed. More extended conclusions will be possible after deeper phylogenetic and statistical analyses.

The 15 AmpF lSTR Identifiler loci (D8S1179, D21S11, D7S820, CSF1PO, D3S1358, THO1, D13S317, D16S539, D2S1338, D19S433, VWA, TPOX, D18S51, D5S818 and FGA) were analyzed in a sample of 136 unrelated Albanian adults from Kosovo. The agreement with HWE was confirmed for all loci with the exception of TPOX (based on the exact test only). The combined power of discrimination (PD) and the combined power of exclusion (PE) for the 15 studied loci were 0.99999999999999997 and 0.9999995, respectively. According to the presented data, FGA proved to be the most informative marker. An interpopulation comparison between Kosovo Albanians and Croatians (as an example of a population from the Balkans) revealed significant differences in four out of nine loci.

The Saami are regarded as extreme genetic outliers among European populations. In this study, a high-resolution phylogenetic analysis of Saami genetic heritage was undertaken in a comprehensive context, through use of maternally inherited mitochondrial DNA (mtDNA) and paternally inherited Y-chromosomal variation. DNA variants present in the Saami were compared with those found in Europe and Siberia, through use of both new and previously published data from 445 Saami and 17,096 western Eurasian and Siberian mtDNA samples, as well as 127 Saami and 2,840 western Eurasian and Siberian Y-chromosome samples. It was shown that the "Saami motif" variant of mtDNA haplogroup U5b is present in a large area outside Scandinavia. A detailed phylogeographic analysis of one of the predominant Saami mtDNA haplogroups, U5b1b, which also includes the lineages of the "Saami motif," was undertaken in 31 populations. The results indicate that the origin of U5b1b, as for the other predominant Saami haplogroup, V, is most likely in western, rather than eastern, Europe. Furthermore, an additional haplogroup (H1) spread among the Saami was virtually absent in 781 Samoyed and Ob-Ugric Siberians but was present in western and central European populations. The Y-chromosomal variety in the Saami is also consistent with their European ancestry. It suggests that the large genetic separation of the Saami from other Europeans is best explained by assuming that the Saami are descendants of a narrow, distinctive subset of Europeans. In particular, no evidence of a significant directional gene flow from extant aboriginal Siberian populations into the haploid gene pools of the Saami was found.

The complexity of interactions between hereditary, environmental and cultural factors in determining human phenotypes is often underestimated in biomedical research. In this paper, we present 33 years of holistic anthropological research that was being conducted since 1971 in the island of Hvar, Croatia. During this period, detailed characterization of migrations, demography, isonymy, linguistic differences, anthropometric traits (head and body dimensions), physiological (cardio-respiratory) properties, quantitative and qualitative dermatoglyphic traits, radiogrammetric metacarpal bone dimensions and genetic traits (classical antigens, HLA diversity, DNA short tandem repeat -STR, mitochondrial DNA and Y-chromosome polymorphisms) was performed. The analysis of this large collection of data using both model-bound and model-free approaches showed that the complexity underlying human biological traits may be considerably greater than generally assumed, which has important implications for design of future studies into genetic determinants of complex traits.

Eight Y chromosome short tandem repeat (STR) polymorphisms (DYS19, DYS388, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393) were analyzed in the sample of 457 unrelated Croatian men. A general STR allelic frequency pattern in Croatians corresponds to other European populations with the exception of the loci DYS19 and DYS389II. The most frequent DYS19 allele was 16, while at the DYS389II the most frequent were alleles 30 and 31. The most frequent Y chromosome haplotype (16-13-13-31-24-11-11-13) was found in 33 individuals (7.22%). One hundred and seventy-four haplotypes (38.07%) were observed in single copies.

Y chromosome variation in 457 Croatian samples was studied using 16 SNPs/indel and eight STR loci. High frequency of haplogroup I in Croatian populations and the phylogeographic pattern in its background STR diversity over Europe make Adriatic coast one likely source of the recolonization of Europe following the Last Glacial Maximum. The higher frequency of I in the southern island populations is contrasted with higher frequency of group R1a chromosomes in the northern island of Krk and in the mainland. R1a frequency, while low in Greeks and Albanians, is highest in Polish, Ukrainian and Russian populations and could be a sign of the Slavic impact in the Balkan region. Haplogroups J, G and E that can be related to the spread of farming characterize the minor part (12.5%) of the Croatian paternal lineages. In one of the southern island (Hvar) populations, we found a relatively high frequency (14%) of lineages belonging to P*(xM173) cluster, which is unusual for European populations. Interestingly, the same population also harbored mitochondrial haplogroup F that is virtually absent in European populations--indicating a connection with Central Asian populations, possibly the Avars.

The aim of this study was to analyse short tandem repeat (STR) variation using the data on nine loci (D3S1358, vWA, FGA, THO1, TPOX, CSF1PO, D5S818, D13S317, D7S820) in the populations from eight villages on the island of Korcula, Croatia, in order to analyse its genetic and population structure. The analysis of STR data in this study indicated an appreciable degree of genetic homogeneity among the studied village populations on the island, even though a so-called 'east-west dichotomy' and differentiation between the inhabitants of the most recent settlement and the remaining ones was indicated with respect to the loci CSF1PO and TPOX, respectively. The validity of STR markers in assessing genetic structure of small populations and especially in determining the relationships among geographically closely related but reproductively isolated groups remains to be further evaluated, especially in terms of a larger number of studied loci in order to possibly find specific markers useful for resolving genetic patterns of variability at regional levels.

The number of previous anthropological studies pointed to very complex ethnohistorical processes that shaped the current genetic structure of Croatian island isolates. The scope of this study was limited to the general insight into their founding populations and the overall level of genetic diversity based on the study mtDNA variation. A total of 444 randomly chosen adult individuals from 32 rural communities of the islands of Krk, Brac, Hvar and Korcula were sampled. MtDNA HVS-I region together with RFLP sites diagnostic for main Eurasian and African mtDNA haplogroups were analysed in order to determine the haplogroup structure. The most frequent haplogroups were "H" (27.8-60.2%), "U" (10.2-24.1%), "J" (6.1-9.0%) and "T" (5.1-13.9%), which is similar to the other European and Near Eastern populations. The genetic drift could have been important aspect in history, as there were examples of excess frequencies of certain haplogroups (11.3% of "I" and 7.5% of "W" in Krk, 10.5% of "HV" in Brac, 13.9% of "J" in Hvar and 60.2% of "H" in Korcula). As the settlements on the islands were formed trough several immigratory episodes of genetically distant populations, this analysis (performed at the level of entire islands) showed greater genetic diversity (0.940-0.972) than expected at the level of particular settlements.

The aim of this study is to analyze short tandem repeat (STR) variation using data on 9 loci (D3S1358, VWA, FGA, THO1, TPOX, CSF1PO, D5S818, D13S317, D7S820) from the subpopulations of 6 villages on the island of Hvar, Croatia. The STR data help us to analyze the genetic structure of Hvar. The analysis of STR data in this study indicated genetic homogeneity among the village subpopulations on Hvar and the lack of the so-called east-west dichotomy, which had been indicated by some previous multidisciplinary anthropological studies. The observed value of GST (0.030) is most probably a consequence of high STR mutation rates, which produce a high level of within-group (village) diversity relative to total diversity of the population. The validity of STR markers in assessing genetic structure of small populations and especially in determining the relationships among closely related and reproductively isolated groups remains to be further evaluated.

The DRB1, DRB3, DRB5, DQA1 and DQB1 allele polymorphisms were analysed in 3 western and 3 eastern villages of the island of Hvar using PCR-SSOP method and 12th International Workshop primers and probes. Three DQB1 alleles (*0304, *0305, *0607) detected in the population of the island of Hvar (HP) have not yet been observed in general Croatian population (GCP). Significant differences were observed between two regions of Hvar for: a) DRB1*0701 allele (p < 0.001), b) DQA1*0201 allele (p < 0.01), and c) DRB1*0101-DQA1*0101-DQB1*0501 haplotypic association (p < 0.05). Two unusual haplotypic associations, which have not yet been described in general Croatian population (GCP), DRB1*0101-DQA1*0102-DQB1*0501 and DRB1*1501-DQA1 *0102-DQB1*0604 were observed in the population from the island of Hvar (HP). Measures of genetic kinship and genetic distances revealed isolation and clusterization which coincides with the known ethnohistorical, as well as biological and biocultural data obtained from a series of previous investigations. The five studied village subpopulations formed two clusters (East-West) to which the far eastern village (with the highest rii of 0.0407) joined later, thus indicating possible impact of historical immigrations from the mainland.