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High-coverage whole-genome sequence studies have so far focused on a limited number of geographically restricted populations, or been targeted at specific diseases, such as cancer. Nevertheless, the availability of high-resolution genomic data has led to the development of new methodologies for inferring population history and refuelled the debate on the mutation rate in humans. Here we present the Estonian Biocentre Human Genome Diversity Panel (EGDP), a dataset of 483 high-coverage human genomes from 148 populations worldwide, including 379 new genomes from 125 populations, which we group into diversity and selection sets. We analyse this dataset to refine estimates of continent-wide patterns of heterozygosity, long- and short-distance gene flow, archaic admixture, and changes in effective population size through time as well as for signals of positive or balancing selection. We find a genetic signature in present-day Papuans that suggests that at least 2% of their genome originates from an early and largely extinct expansion of anatomically modern humans (AMHs) out of Africa. Together with evidence from the western Asian fossil record, and admixture between AMHs and Neanderthals predating the main Eurasian expansion, our results contribute to the mounting evidence for the presence of AMHs out of Africa earlier than 75,000 years ago.

It is commonly thought that human genetic diversity in non-African populations was shaped primarily by an out-of-Africa dispersal 50-100 thousand yr ago (kya). Here, we present a study of 456 geographically diverse high-coverage Y chromosome sequences, including 299 newly reported samples. Applying ancient DNA calibration, we date the Y-chromosomal most recent common ancestor (MRCA) in Africa at 254 (95% CI 192-307) kya and detect a cluster of major non-African founder haplogroups in a narrow time interval at 47-52 kya, consistent with a rapid initial colonization model of Eurasia and Oceania after the out-of-Africa bottleneck. In contrast to demographic reconstructions based on mtDNA, we infer a second strong bottleneck in Y-chromosome lineages dating to the last 10 ky. We hypothesize that this bottleneck is caused by cultural changes affecting variance of reproductive success among males.

Mutations of CFTR gene are identified as the molecular basis of cystic fibrosis (CF) disease, but there are also other "modifier" genes, that influence the pathogenesis of the patients with CF. One such modifier genes is ß2-adrenoreceptor gene (ADRB2). The aim of this study is the identification of polymorphic variants of this gene, in the locus Gln27Glu, in Albanian CF patients, in order to elucidate possible relations with clinical signs of the patients. We analyzed 47 patients with CF, which have the same genotype for CFTR gene, delF508 homozygous. DNA was extracted using standard methods from 5 ml of blood samples with EDTA. To identify genetic variants of this gene we used AS-PCR method and gel electrophoresis. Calculation of allele frequencies was done according to formulas in genetics of population. The method used for this study (AS - PCR) was very effective, with high sensitivity and low cost. We found out that in Gln27Glu locus, the frequency of Gln27 and Glu27 alleles were 0,62 and 0,38 respectivily. After genotyping ADRB2 gene in locus 27 for each patient, we defined groups of patients with the same genotype. In future, we will use subgroups of CF patients with the same genotypes for ADBR2 gene, in order to analyze the relationship between genotypes Gln27Glu and clinical parameters of CF disease. Identification of polymorphic variants of B2AR modifier gene in CF patients, could be useful in predicting clinical status of the patients and can help to perform differentiated treatments. [ABSTRACT FROM AUTHOR]

The objective of this study was the identification of the polymorphism of kappa-casein gene in two autochthonous goat breeds and the investigation of the relationship of k-casein genotypes with physicochemical composition of the milk. For this purpose, blood samples were collected from 25 individuals of each goat breed, Dukati and Kallmeti and genomic DNA was extracted. A protocol for rapid simultaneous genotyping of six κ-CN variants, the primer extension method, was used. In Dukati breed were found alleles B and C, with allele B frequency of 82% and allele C frequency of 18%. In Kalimeti breed were found alleles B and A, with variant B frequency of 84% and variant A frequency of 16%. All individuals were genotyped and divided in two groups. Milk samples from the individuals for each goat breed, were collected during the lactation and were analyzed for physicochemical characteristics and rheological characteristics. The average values of the group for each parameter were determined and conipared to the same figures of the other group. The differences between BB group and BC and AB groups regarding the average values of 7 parameters were analyzed by F test to determine the significance of the differences. It was observed that individuals with genotype BB of the kappa-casein gene presented higher fat percentage than individuals of other group, BC or BA genotypes, in both goat breeds, Dukati and Kallmeti. The kappa-casein gene BB genotype showed a greater influence on fat percentage and also on tCoag in both breeds. The present study was the first attempt to determine the polymorphism of kappa-casein gene and the association of the κ-casein genotypes with phenotypic data. [ABSTRACT FROM AUTHOR]

Background: Determination of Rhesus (Rh) status is of critical importance in the field of both transfusion and obstetric medicine. As the distribution of Rh phenotypes was unknown in the Albanian population, we investigated the donor population in Albania to estimate the prevalence of each phenotype, as well as to identify and characterise the variants at the molecular level., Materials and Methods: A total of 38,836 blood donors were phenotyped for Rh D, C, c, E and e antigens by routine serological methods, and samples with reduced D antigen expression underwent molecular characterisation by a Tm-shift genotyping method and direct sequencing., Results: Among all donors 89.00% and 10.86% were D-positive and D-negative, respectively, while 0.14% (n=55) of the donors were found to be weak D-positive. Overall 45/55 samples (81.8%) were resolved by Tm-shift screening, showing that approximately 67% of the variant D alleles were weak D type 1, while weak D type 3 (9.1%) and weak D type 2 (3.6%) were less common. A novel c.932A>G (p.Y311C) variant was also found in the heterozygous state by direct sequencing., Discussion: This extensive study reveals the distribution of Rh phenotypes in the Albanian population, the low prevalence of individuals with a weak D phenotype, and the specific pattern of distribution of the three most common variant alleles in this Caucasian population.

We characterized a set of 100 Mycobacterium tuberculosis complex clinical isolates from tuberculosis (TB) patients in Albania, typing them with a 24-locus variable-number tandem-repeat-spoligotyping scheme. Depending on the cluster definition, 43 to 49 patients were distributed into 15 to 16 clusters which were likely to be epidemiologically linked, indicative of a recent transmission rate of 28 to 34%. This result suggests that TB is under control in Albania. However, two multidrug-resistant (MDR) Beijing genotypes harboring the same S531A mutation on the rpoB gene were also found, suggesting a potential recent transmission of MDR TB. Three brand new genotypes, Albania-1 to Albania-3, are also described.