Faculty of Medicine

Objective: The aim of our study was to investigate whether methylenetetrahydrofolate reductase (MTHFR) gene variant (MTHFR 677C9T) and thymidylate synthase (TS) gene variants (TS enhancer region [TSER] and TS 1494del6) confer a risk for premature ovarian failure (POF).

The Former Yugoslav Republic of Aim: MHC class I and II genes form one of the most polymorphic genetic systems known to date, the polymorphism largely consisting of single nucleotide polymorphisms. None of the current DNA techniques offers ambiguity-free MHC typing, therefore defining strategies to resolve allele ambiguities remains to be a great challenge. The aim of the study was to investigate the occurrence of ambiguous allele combinations at the allele group level of HLA -A, -C and -B loci in Macedonian population.

A total of 850 persons from the Republic of Macedonia, divided in the four groups, were DNA-HLA genotyped: 1. Donors of the Macedonian Donor Registry (220); 2. Patients for bone marrow transplantation and related potential donors (350); 3. Patients with rheumatoid arthritis, tuberculosis, cardiomyopaties and other diseases (150); and 4. Ambiguity resolution of the genotypes (130). Class I HLA genes (A, C, B, and DQB1) were typed by Reverse Line Strip Typing (RLS); Class II HLA gene (DRB1) were typed by Sequence Based Typing (SBT). The main results of the project are: a) Creation and legislation of Macedonian Donor Registry, and Macedonian Human DNA Bank; b) HLA typing of unrelated healthy persons for class I HLA-A, -C, and -B, and class II HLA-DRB1; c) HLA genotyping of blood related samples for Bone Marrow Transplantation; d) Association analysis of HLA alleles with Rheumatoid Arthritis (HLA-DRB1, and HLA-B27), and with Pulmonary Tuberculosis (HLA-DQB1); e) Evaluation of allele and genotype ambiguities for HLA class I, and HLA class II, as well as resolution of HLA class I and class II ambiguities; f) Introduction and establishment of sequence specific primers (SSP) method for resolving HLA class II ambiguities in patients with Rheumatoid Arthritis.

Background. The self-evaluation is a process that provides a realistic reflection on the work and perspectives of a higher level educational institution, such as the Faculty of Medicine in Skopje. Thus, it is necessary to identify the positive and especially the negative elements of the overall functioning of the organization in order to suggest measures and professional staff to accomplish them.

To determine the frequency distribution of apoprotein(a) isoforms in patients with insulin-dependent (IDDM) and non-insulin-dependent (NIDDM) diabetes mellitus and healthy subjects. Method. We separated and visualized 5 apo(a) isoforms in 40 patients with IDDM (12 men aged 48.00 ± 4.59 and 28 women aged 52.37 ± 8.21), 65 patients with NIDDM (26 men aged 61.88 ± 9.25 and 39 women aged 60.15 ± 7.98), and 182 healthy subjects, using 3-15% gradient sodium dodecyl sulfate polyacrylamide gel electrophoresis, followed by immunoblotting. Results. The frequency distribution of apo(a) isoforms was very similar in patients with diabetes mellitus and the control group. Atherogenic low molecular weight (LMW) S1 apo(a) isoform was more frequent in patients with IDDM (7.5%) and NIDDM (6.15%) than in the control group (0.78%). LMW S1 apo(a) isoform in patients with IDDM (relative risk [RR], 6.86; 95% confidence interval [CI], 1.19-25.21; p<0.001) and patients with NIDDM (RR, 7.04; 95% CI, 1.40-35.40; p=0.0057) as well as high molecular weight >S4 apo(a) isoform in patients with NIDDM (RR, 2.39; 95% CI, 1.28-5.21; p=0.0067) significantly increased the risk for the development of atherosclerosis. Mean molecular weight of S3, S1, and B apo(a) isoforms was higher in patients with IDDM and NIDDM than in the healthy subjects carriers of the same isoforms, but this difference was not statistically significant. We estimated high inverse statistical correlation between apo(a) size (kDa) and plasma lipoprotein(a) concentration in all study groups, patients with IDDM (p<0.001), patients with NIDDM (p<0.001), and healthy subjects (p<0.01). Conclusion. Not only the increased plasma Lp(a) levels, but also apoprotein(a) isoforms may play an important role as a risk factor for the development of atherosclerosis in patients with diabetes mellitus.

Lipoprotein(a) is composed of apoB-100 and the unique protein apolipoprotein(a). Plasma levels of Lipoprotein(a) are determined largely by variation in the gene that encodes it. High plasma levels and small-sized apolipoprotein(a) isoforms are thought to be an independent risk factor for development of atherosclerosis. Children with diabetes mellitus are prone to early development of atherosclerosis. We investigated apolipoprotein(a) polymorphisms and lipoprotein(a) plasma concentrations in 60 normoalbuminuric children with diabetes mellitus type 1 and in 100 healthy children aged between 9 and 17 years. Sodium dodecyl sulphate polyacrylamide gel electrophoresis was used for separation of apolipoprotein(a) isoforms. Individuals expressed a single band (homozygotic), a double band (heterozygotic) or no band (null phenotype). In both groups single-banded phenotypes were more common than double-banded phenotypes: 50.0 % vs. 46.7 % for patients and 53.0 % vs. 43.0 % for controls. A higher prevalence of large size (≥22 Kringle IV repeats) apolipoprotein(a) isoforms, associated with lower lipoprotein(a) concentrations, was detected in the patients and in the controls. Most plasma lipoprotein(a) levels were in the low range. Lipoprotein(a) concentrations below the risk limit of 30 mg/dL were present in 90 % of subjects. The comparison of the two groups showed no significant difference between their mean and median plasma concentration of lipoprotein(a).

During the 15th International Histocompatibility and Immunogenetics Workshop (IHIWS), 14 human leukocyte antigen (HLA) laboratories participated in the Analysis of HLA Population Data (AHPD) project where 18 new population samples were analyzed statistically and compared with data available from previous workshops. To that aim, an original methodology was developed and used (i) to estimate frequencies by taking into account ambiguous genotypic data, (ii) to test for Hardy–Weinberg equilibrium (HWE) by using a nested likelihood ratio test involving a parameter accounting for HWE deviations, (iii) to test for selective neutrality by using a resampling algorithm, and (iv) to provide explicit graphical representations including allele frequencies and basic statistics for each series of data. A total of 66 data series (1–7 loci per population) were analyzed with this standard approach. Frequency estimates were compliant with HWE in all but one population of mixed stem cell donors. Neutrality testing confirmed the observation of heterozygote excess at all HLA loci, although a significant deviation was established in only a few cases. Population comparisons showed that HLA genetic patterns were mostly shaped by geographic and/or linguistic differentiations in Africa and Europe, but not in America where both genetic drift in isolated populations and gene flow in admixed populations led to a more complex genetic structure. Overall, a fruitful collaboration between HLA typing laboratories and population geneticists allowed finding useful solutions to the problem of estimating gene frequencies and testing basic population diversity statistics on highly complex HLA data (high numbers of alleles and ambiguities), with promising applications in either anthropological, epidemiological, or transplantation studies.

Several studies have investigated the genetic polymorphisms for cytokines as potential genetic markers for periodontitis. The aim of this study was to determine the prevalence of IL1 cluster genes polymorphisms and their association with chronic periodontitis in the Macedonian population. The group of 114 unrelated Macedonian subjects with chronic periodontitis and 301 periodontitis-free Macedonian subjects were studied. DNA was isolated from peripheral blood leukocytes by phenol-chloroform extraction method. Cytokine genotyping was performed by PCR-SSP. The population genetics analysis package (PyPop) was used for analysis of the cytokine data for this report. Crude odds ratio (OR) was calculated as estimates of the relative risk with 95 % confi dence interval (CI). Genotype frequency of IL1B -511/C:T was signifi cantly higher in patients with periodontitis than in controls (OR=2.11, 95 % CI=1.35-3.32, p=0.001). IL1 cluster gene haplotype frequencies of TTTCT and TCTTT were associated with higher risk for periodontitis (OR=5.06, 95 % CI=1. p<0.0014 and OR=8.35, p<0.002, respectively). No signifi cant association of IL1 composite genotype (IL1 -889A:IL1B +3962) with periodontitis in Macedonians was found. The latter association was found to be signifi cant in genotype IL1B -511/C:T, haplotype TTTCT, and haplotype TCTTT, but without signifi cant association in IL1 composite genotype (Tab. 5, Ref. 43). Full Text in PDF www.elis.sk.

The aim of this study was to analyze 22 cytokine polymorphisms in the Roma population from the Republic of Macedonia. The Roma population consists of 77 healthy unrelated individuals, residents of different geographical regions of the Republic of Macedonia (Skopje, Gostivar, and Kochani).