Author Correction: Sex-biased patterns shaped the genetic history of Roma.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Sex-biased patterns shaped the genetic history of Roma.

The Roma population is a European ethnic minority characterized by recent and multiple dispersals and founder effects. After their origin in South Asia around 1,500 years ago, they migrated West. In Europe, they diverged into ethnolinguistically distinct migrant groups that spread across the continent. Previous genetic studies based on genome-wide data and uniparental markers detected Roma founder events and West-Eurasian gene flow. However, to the best of our knowledge, it has not been assessed whether these demographic processes have equally affected both sexes in the population. The present study uses the largest and most comprehensive dataset of complete mitochondrial and Y chromosome Roma sequences to unravel the sex-biased patterns that have shaped their genetic history. The results show that the Roma maternal genetic pool carries a higher lineage diversity from South Asia, as opposed to a single paternal South Asian lineage. Nonetheless, the European gene flow events mainly occurred through the maternal lineages; however, a signal of this gene flow is also traceable in the paternal lineages. We also detect a higher female migration rate among European Roma groups. Altogether, these results suggest that sociocultural factors influenced the emergence of sex-biased genetic patterns at global and local scales in the Roma population through time.

Cystic Fibrosis Mutation Spectrum in North Macedonia: A Step Toward Personalized Therapy.

The most prevalent "rare" disease worldwide, cystic fibrosis (CF), is an autosomal recessive multisystem disease, caused by mutations in the CFTR gene. The knowledge of CFTR mutations present in certain population is important for designing a simple, fast and cost-effective genetic testing approach, also for better management of CF patients, including the administration of novel targeted therapies. Here, we present genetic results of 158 unrelated CF patients from the National CF Registry of the Republic of North Macedonia. Initially, patients were screened for the 11 most common CF mutations. Additional CF mutations and large deletions/duplications in the CFTR gene were analyzed using commercial kits. If the genotype was undetermined, all CFTR exons were analyzed using Sanger DNA sequencing or next generation sequencing (NGS) (since 2014). The most common CF mutation, c.l521_ 1523del (legacy name F508del), was found with an overall incidence of 75.9%. Additionally, 26 other pathogenic variants and three large deletions were identified in the CFTR gene as a genetic cause of CF. Two of these, c.1070 C>T (p.Ala357Val) and c.2779_2788dup CTTGCTATGG (p.Gly930AlafsTer48), were novel. According to the distribution and prevalence of the pathogenic variants detected in our patients, a fast and cost-effective method, based on a single base extension was designed as a first-line CF genetic test with a 90.0% detection rate within our population. Furthermore, the knowledge of CFTR mutation classes in our CF patients represents the first step toward personalized therapy for CF in our country.

CYP2D6 allele distribution in Macedonians, Albanians and Romanies in the Republic of Macedonia.

Cytochrome P450 2D6 (CYP2D6) is an enzyme of great importance for the metabolism of clinically used drugs. More than 100 variants of the CYP2D6 gene have been identified so far. The aim of this study was to investigate the allele distribution of CYP2D6 gene variants in 100 individuals of each of the Macedonian, Albanian and Romany population, by genotyping using long range polymerase chain reaction (PCR) and a multiplex single base extension method. The most frequent variants and almost equally distributed in the three groups were the fully functional alleles *1 and *2. The most common non functional allele in all groups was *4 that was found in 22.5% of the Albanians. The most common allele with decreased activity was *41 which was found in 23.0% of the Romany ethnic group, in 11.0% of the Macedonians and in 10.5% of the Albanians. Seven percent of the Albanians, 6.0% of the Romani and 4.0% of the Macedonians were poor metabolizers, while 5.0% of the Macedonians, 1.0% of Albanians and 1.0% of the Romanies were ultrarapid metabolizers. We concluded that the CYP2D6 gene locus is highly heterogeneous in these groups and that the prevalence of the CYP2D6 allele variants and genotypes in the Republic of Macedonia is in accordance with that of other European populations.

Genetics of non syndromic hearing loss in the republic of macedonia.

Hearing impairment is the most common sensory deficit in humans affecting 1 in 1000 newborns. When present in an infant, deafness may have dramatic effects on language acquisition, seriously compromising the quality of their life. Deafness is influenced by both genetic and environmental factors, with inherited causes as the most prominent etiological factor in deafness in developed countries. The genetic basis of hearing loss is complex with numerous loci and genes underlying hereditary sensoryneural non syndromic hearing loss (NSHL) in humans. Despite the wide functional heterogeneity of the genes, mutations in the GJB2 gene are found to be the most common cause of sporadic and recessive NSHL in many populations worldwide. Molecular characterization of deafness in the Republic of Macedonia was performed in 130 NSHL profoundly deaf children from different ethnic origins. Molecular studies included direct sequencing of the GJB2 gene and specific polymerase chain reaction (PCR) analyses for the del(GJB6-D13S1830) mutation. Five common mitochondrial DNA (mtDNA) mutations [A1555G, 961delT+ C(n), T1095C, C1494T and A827G] were also analyzed using the SNaPShot method. In preliminary studies, GJB2 gene mutations were found in 36.4% of analyzed patients, with predominance of 35delG in Macedonian and Albanian patients and W24X in Gypsy patients, respectively. No del(GJB6-D13S1830) mutation was found. None of the analyzed deafness-associated mutations in mtDNA were identified in the studied patients.

Study of the hepatitis C virus in the republic of macedonia.

Hepatitis C virus (HCV) is a major public health problem. It is a leading cause of chronic liver disease and the most common indication for liver transplantation. The therapy for eradication of HCV infection is successful in only 50.0-80.0% of patients and is highly dependent on the HCV genotype. Molecular detection and characterization of HCV in the Republic of Macedonia started in 1990. Since then, more than 4000 samples have been analyzed at the Research Centre for Genetic Engineering and Biotechnology (RCGEB) "Georgi D. Efremov," Skopje, Republic of Macedonia. The prevalence of HCV infections in the healthy population of the Republic of Macedonia was found to be 0.4%, while it varies between 23.0 and 43.0% in different at-risk groups of patients. The prevalence of HCV genotypes, according to associated risk factors in HCV infected patients from the Republic of Macedonia, was analyzed. We found genotype 1 to be predominant in a group of hemodialysis patients, while genotype 3 was predominant in intravenous (IV) drug users. Association of six polymorphisms in the Oligoadenylate synthetase (OASL)-like interferon-stimulated gene with a sustained virological response was also analyzed. Our preliminary results suggest that non ancestral alleles in four of the six studies polymorphisms in OASL gene are associated with sustained virological response among HCV infected patients in R. Macedonia.

Three novel point mutations causing haemophilia A.

Haemophilia A is an X-linked bleeding disorder caused by mutations in the factor VIII gene. In our efforts to elucidate molecular defects in the haemophilia A patients from the Republic of Macedonia, we employed nonradioactive single-strand conformation polymorphism analysis followed by direct sequencing, for identifying point mutations in the factor VIII gene. In the present study we report the detection of three novel missense mutations: Met19 --> Arg; Ala78 --> Pro and Cys2174 --> Gly, all causing haemophilia A.