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The presence of null alleles may affect the outcome of stem cell transplantation. HLA-C*04: 09N was defined as 'common' with a frequency of 2-5/1000 in Caucasians, and its presence is routinely tested as part of haplotypes HLA-A*02:01/A*23:01-B*44:03- DRB1*07:01- DQB1*02:01. We aimed to investigate HLA-C*04: 09N in a representative Hungarian cohort. HLA-typing data of 7345 unrelated persons were analyzed. The presence of HLA-C*04: 09N was excluded in 157 chromosomes with either serology typing or with an allele-specific polymerase chain reaction for HLA-C*04: 09N. HLA-C*04: 09N was identified in a single chromosome with HLA-A*02, B*44, C*04, DRB1*07 resulting in a HLA-C*04: 09N allele frequency of 0.0068% (1/14,690). This is approximately a 10- to 40-fold lower frequency compared with the previous data. Our results emphasize the need of precise local population-specific HLA-data, allowing appropriate modifications of local HLA-typing protocols. [ABSTRACT FROM AUTHOR]

Purpose: In previous studies the NFKBIA 3'UTR (untranslated region) AA genotype was associated with Crohn's disease (CD), while the NFKB1-94ins/delATTG mutation increased the risk for ulcerative colitis (UC). The aim of our study was to investigate these two polymorphisms and patients' response to medical therapy and/or disease phenotype in Hungarian inflammatory bowel disease (IBD) patients.Methods: NFKBIA 3'UTR- and NFKB1-94ins/delATTG polymorphisms were investigated in 415 unrelated IBD patients (CD: 266 patients, mean age 35.2 +/- 12.1 years, duration 8.7 +/- 7.5 years; UC patients: 149, mean age 44.4 +/- 15.4 years, duration 10.7 +/- 8.9 years) and 149 controls by PCR-restriction fragment length polymorphism (RFLP) analysis. Detailed clinical phenotypes were determined by reviewing the medical charts.Results: The NFKBIA 3'UTR and NFKB1-94ins/delATTG genotypes and allele frequencies were not significantly different among IBD and controls. In patients with UC, the 3'UTR GG genotype was associated with extensive colitis (55.3 vs. 29.4%, odds ratio 2.97, 95% confidence interval 1.45-6.08). The presence of variant alleles did not predict response to steroids, infliximab, or need for surgery.Conclusions: The NFKBIA 3'UTR GG genotype was associated with an increased risk for extensive colitis in Hungarian patients. In contrast, variant alleles did not predict response to medical therapy or need for surgery. [ABSTRACT FROM AUTHOR]

Abstract: Background: North American and European genome-wide association scans have identified ATG16L1 and IL23R as novel inflammatory bowel disease (IBD) susceptibility genes and subsequent reports confirmed these findings in large independent populations. The aims of this study were to investigate the association and examine genotype–phenotype relationships in a Hungarian IBD cohort. Methods: 415 unrelated IBD patients (CD: 266, age: 35.2±12.1 years, duration: 8.7±7.5 years and UC: 149, age: 44.4±15.4 years, duration: 10.7±8.9 years) and 149 healthy subjects were investigated. IL23R Arg381Gln (R381Q, rs11209026) and ATG16L1 Thr300Ala (T300A, rs2241880) polymorphisms were tested using LightCycler allele discrimination method. Detailed clinical phenotypes were determined by reviewing the medical charts. Results: The association between IL23R rs11209026, ATG16L1 rs2241880 and CD was confirmed (ORIL23R381Q: 0.38, 95% CI: 0.16–0.87; ORATG16L1300AA: 1.86, 95% CI: 1.04–3.40). No difference was found between patients with UC and either controls or CD. In CD, IL23R 381Gln heterozygosity was associated with inflammatory disease (70% vs. 34%, p =0.037), while disease restricted to the colon was more prevalent in patients with the ATG16L1 300Ala/Ala homozygosity (33.3% vs. 21.1%, p =0.036). In addition, carriage of the variant alleles did not predict response to steroids, infliximab or need for surgery. Conclusions: We confirmed that ATG16L1 and IL23R are susceptibility loci for CD in Hungarian CD patients. Further studies are needed to confirm the reported phenotype–genotype associations found in this study. [Copyright &y& Elsevier]

Our aim was to set up a protocol in order to provide carrier and prenatal diagnosis to Hungarian haemophilia A (HA) and B (HB) patients and their relatives. For HA, a combination of direct mutation detection and some indirect marker analyses were used: the detection of the inversion mutation and analysis of three polymorphisms, BclI, IVS13 (CA)n and P39(CA)n. In severe cases, direct mutation detection was performed first. In inversion-negative severe cases and in moderate and mild cases, indirect methods were used. For carrier and prenatal diagnosis in HB, four polymorphisms, DdeI, TaqI, XmnI, and HhaI were examined. Our DNA bank contains samples from 50 HA families (34 severe, 15 moderate and one mild) and seven HB families from different parts of the country. In 100% of the HA cases either the gene inversion and/or at least one of the polymorphisms was found to be informative for carrier or prenatal diagnosis. In the HB cases, an informative marker was found in 95% of the cases (19 of 20). We conclude that these strategies are sufficient to make genetic diagnosis available to almost all HA and HB families in the region. This approach is highly informative and cost-effective, so it can be very useful in countries where direct sequencing of genes for factor VIII and IX is not available for routine diagnosis. [ABSTRACT FROM AUTHOR]

Abstract: One hundred and seventy three entire mtDNA control region sequences were generated and analyzed in a population sample from Ashkenazi Jews living in Hungary. The control region was amplified in one piece and sequenced with different sequencing primers. Sequence evaluation was performed twice and validated by a third senior scientist. Phylogenetic analyses were used for quality assurance purposes and for the determination of the haplogroup affiliation of the samples. Upon publication, the population data are going to be available in the EMPOP database (www.empop.org). [Copyright &y& Elsevier]

Hereditary angioneurotic edema (HAE) is an autosomal dominant disorder characterized by episodic local subcutaneous and submucosal edema caused by the deficiency of activated C1 esterase inhibitor protein (C1-INH, type I (C1NH): reduced serum antigen level, type II: reduced activity and normal serum antigen level). The aim of the present study was to determine the disease-causing mutations in the C1INH gene (SERPING1) among Hungarian HAE-patients. The estimated number of affected HAE-families in Hungary is 40–50, out of which 26 families (type I:23, type II:3) managed in a single center were enrolled in the current study. To detect large deletions/insertions, we used Southern-blotting analysis followed by real time PCR based gene dosage analysis. In the absence of large structural changes, we employed direct sequencing covering the whole coding region and splicing sites of the C1INH gene. Large deletions were detected in 4/23 (17.4%) type I families. We found the g.16788C>T (p.Arg444Cys) mutation in each 3, type II HAE-families. In the remaining type I families, 13 previously unreported mutations (g.638G>A, g.2238C>T, g.2534_2535delCT, g.2579_2620del42, g.2533G>A, g.2695G>A, g.2696_2697insT, g.4467C>T, g.14224A>T, g.14107delA, g.16749_;16775dup, g.16810T>A, g.16885C>G) were detected in 16 families affecting primarily exon 3 (6/13) of the C1INH gene. In the 3 remaining families, known mutations were identified affecting primarily exon 8 (2/3). © 2003 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Abstract: Background: Based on national ethics committee permission, the procedure of urgent immunogenetics testing prior to cadaveric kidney transplantation was changed in Hungary from January 1, 2011 allowing HLA typing of the donor and prospective crossmatching using peripheral blood samples from the donor prior to the definitive declaration of brain death. The aim of the current study was to compare key indicators of transplantation primarily cold ischemic time [CIT], between time periods with outcomes. Methods: The following indicators were systematically collected prospectively and retrospectively for each deceased heart-beating donor transplantation between January 1, 2010 and October 31, 2010 (n = 114) versus January 1, 2011 and October 31, 2011 (n = 91): CIT for the first and second kidney; laboratory turnaround times (TAT), and time for final preparation of the selected recipient. Results: As a result of the new procedure, the CIT for the first kidney decreased from 16.5 ± 3.5 to 12.4 ± 3.2 hours (P < .001). Similarly, for the second kidney the parameters were a 19.8 ± 3.4 versus 16.0 ± 3.8 hours (P < .001). As a consequence of more hands-on time in the laboratory, the TAT increased from 5.6 ± 0.8 hours to 7.2 ± 1.1 hours (TAT1) followed by an additional 4.2 ± 1.0 hours (TAT2). We also compared the times necessary for preparation of immunologically suitable recipients for transplantation, namely, 9.5 ± 2.3 hours in the earlier system, increasing to 15.5 ± 4.3 hours during the new procedure. Conclusion: As a consequence of the procedural change, the CIT parameter decreased significantly for both kidneys, which may have contributed to improved short-term outcomes of transplantation. The time available for final preparation of selected recipients was increased allowing improvements in CIT. [Copyright &y& Elsevier]

Background & Aims: Pattern recognition receptors (PRRs) have a key role in the innate host defense. Functional polymorphisms of various PRRs have been established to contribute to an increased susceptibility to spontaneous bacterial peritonitis (SBP). Their role in the development of cirrhosis-associated bacterial infections (BI), beyond SBP or progressive disease course related to pathological bacterial translocation (BT) remains unknown., Methods: Three hundred and forty-nine patients with cirrhosis were genotyped for common NOD2 (R702W, G908R and L1007PfsinsC), TLR2 (-16934T>A), and TLR4 (D299G) variants. Incidence of BIs, decompensating events and liver-related death were assessed in a 5-year follow-up observational study. Pathological BT was assessed based on the presence of antimicrobial antibodies or lipopolysaccharide-binding protein (LBP) level., Results: In patients with ascites (n = 88) only NOD2 gene variants were associated with an increased cumulative probability of SBP (76.9% ± 19.9%) compared to wild-type (30.9% ± 6.9%, P LogRank  = .047). Individual or combined PRR genetic profiles were associated with the risk of non-SBP type BI. Advanced disease stage (HR [95% CI]: 2.11 [1.38-3.25]) and prior history of a BI episode (HR: 2.42 [1.58-3.72]) were the major clinical risk factors of a subsequent BI. The risk of a non-SBP type BI in patients with advanced disease and a prior BI was even higher (HR: 4.74 [2.68-8.39]). The frequency of antimicrobial antibodies and LBP levels did not differ between various PRR genotypes. Correspondingly, PRR genetic profile was not able to predict the long-term disease course., Conclusions: In cirrhosis, functional polymorphisms of PRRs did not improve the identification of patients with high risk of BI beyond SBP or progressive diseases course., (© 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Systematic analyses of human leukocyte antigen (HLA) profiles in different populations may increase the efficiency of bone marrow donor selection and help reconstructing human peopling history. We typed HLA-A, -B, and -DRB1 allele groups in two bone marrow donor cohorts of 2402 Hungarians and 186 Hungarian Gypsies and compared them with several Central-European, Spanish Gypsy, and Indian populations. Our results indicate that different European Gypsy populations share a common origin but diverged genetically as a consequence of founder effect and rapid genetic drift, whereas other European populations are related genetically in relation to geography. This study also suggests that while HLA-A accurately depicts the effects of genetic drift, HLA-B, and -DRB1 conserve more signatures of ancient population relationships, as a result of balancing selection., (© 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Introduction: Histamine N-methyltransferase (HNMT) is the main metabolizing enzyme of histamine. Histamine modulates immune responses and plays a role in the pathogenesis of autoimmune disorders., Methods: The non-synonymous HNMT C314T polymorphism and the A939G single-nucleotide polymorphism (SNP) influencing HNMT mRNA stability were genotyped in 213 patients with myasthenia gravis (MG) and 342 healthy controls., Results: The carrier frequency of the A allele of the A939G SNP was over-represented among patients with anti-AchR and anti-Titin antibodies (P = 0.05 and P = 0.004, respectively); the presence of the minor G allele was protective against anti-AchR and anti-Titin positive MG (OR = 0.67 and OR = 0.54, respectively). The combination of the G allele carrier status with wild-type C314C homozygosity was also protective against MG (OR = 0.55, P = 0.008) and against the development of anti-AchR antibodies (OR = 0.37, P = 0.01)., Discussion: The A939G HNMT polymorphism is associated with autoimmune MG, while no association with C314T SNP was found., (Copyright © 2013 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.)

Background: Additional chromosome abnormalities (ACAs), mutations of the BCR-ABL tyrosine kinase domain (TKD) and BCR-ABL splice variants may cause resistance to first- and second-generation tyrosine kinase inhibitors (TKIs) in chronic myelogenous leukemia (CML) and Philadelphia-positive (Ph+) acute lymphoid leukemia (ALL)., Methods: Karyotyping and BCR-ABL TKD mutation screening were performed in 71 imatinib-resistant CML patients and 6 Ph+ ALL patients. A total of 56 out of these 77 patients received second-generation TKI., Results: ACAs were present in 30 of 65 imatinib-resistant patients (46%). In 27 of 74 imatinib-resistant patients (36%), 15 different BCR-ABL TKD mutations were detected. Mutations were found in 25% of chronic-phase patients (12/47), 33% of accelerated-phase patients (5/15), 71% of blast crisis CML patients (5/7) and 100% of ALL patients. In nilotinib-resistant patients, Y253H, T315I and F359I/V mutations were detected; in dasatinib-resistant patients, L248M, E279K and T315I mutations were detected. T315I was found more frequently in patients on dasatinib than on imatinib therapy. The presence of ACAs predicted shorter survival during first- and second-generation TKI therapy, while TKD mutations only influenced survival during second-generation TKI therapy., Conclusion: For patients with TKI resistance, mutation and ACA screening may play a role in identifying patients with poorer prognosis., (Copyright © 2011 S. Karger AG, Basel.)

Aim: To investigate variants of immunity-related GTPase family M (IRGM) and NKX2-3 genes and genotype-phenotype in Eastern European patients with inflammatory bowel disease (IBD)., Methods: We analyzed 1707 Hungarian and Czech subjects with Crohn's disease (CD) (n = 810, age: 37.1 ± 12.6 years, duration: 10.7 ± 8.4 years) and ulcerative colitis (UC) (n = 428, age: 43.7 ± 15.0 years, duration: 12.6 ± 9.9 years), as well as 469 healthy controls. IRGM rs13361189, NKX2-3 rs10883365 and ECM1 rs13294 polymorphisms were tested by LightCycler allele discrimination. Detailed clinical phenotypes were determined by reviewing the medical charts., Results: NKX2-3 rs10883365 variant allele was associated with increased risk for CD (P = 0.009, OR = 1.24, 95% CI = 1.06-1.48) and UC (P = 0.001, OR = 1.36, 95% CI = 1.13-1.63), whereas variant IRGM allele increased risk for CD (P = 0.029, OR = 1.36, 95% CI = 1.03-1.79). In contrast, ECM1 rs13294 was not associated with either CD or UC. In CD, the variant IRGM allele was associated with a colon-only location (P = 0.02, OR = 1.62, 95% CI = 1.07-2.44), whereas in UC, the ECM1 variant was associated with cutaneous manifestations (P = 0.002, OR = 3.36, 95% CI = 1.48-7.63). Variant alleles did not predict resistance to steroids or azathioprine, efficacy of infliximab, or need for surgery., Conclusion: NKX2-3 and IRGM are susceptibility loci for IBD in Eastern European patients. Further studies are needed to confirm the reported phenotype-genotype associations.

Loss-of-function mutations of ABCC6 cause pseudoxanthoma elasticum (PXE). This Mendelian disorder is characterized by elastic calcification leading to dermal, ocular, and cardiovascular symptoms like coronary artery disease (CAD) and stroke. Although PXE is a recessive disease, microscopic dermal lesions, serum alterations, and higher anecdotal incidence of stroke or CAD among carriers were reported. Here we investigated the association of the c.3421C>T loss-of-function mutation of ABCC6 and CAD and stroke. A previous study demonstrated the association of the c.3421C>T mutation with CAD; however, the frequency found in the control population was unexpectedly high, contradicting, thus, the prevalence of PXE. In the present study, genomic DNA from 749 healthy blood donors was used as control, while 363 and 361 patients suffering from stroke and CAD were investigated, respectively. One carrier was found in our control group, which is in accordance with the reported prevalence of this mutation. No significant association was found between carrier status and stroke in our cohort. In contrast, a significant association of carrier status and CAD was observed (5/361 carriers: p = 0.016, odds ratio [OR] = 10.5). We propose that carriers of ABCC6 loss-of-function mutations benefit from CAD prevention therapy.

Aim: To determine the prevalence of a new set of anti-glycan and anti-outer membrane protein (anti-OMP) antibodies in a Hungarian cohort of adult Celiac disease (CD) patients., Methods: 190 consecutive CD patients [M/F: 71/119, age:39.9 (SD:14.1) years], 100 healthy, and 48 gastrointestinal controls were tested for glycan anti-Saccharomyces cerevisiae (gASCA), anti-laminaribioside (ALCA), anti-chitobioside, anti-mannobioside, anti-OMP antibodies and major NOD2/CARD15 mutations. Thirty out of 82 CD patients enrolled at the time of diagnosis were re-evaluated for the same antibodies after longstanding gluten-free diet (GFD)., Results: 65.9% of the CD patients were positive for at least one of the tested antibodies at the time of the diagnosis. Except anti-OMP and ALCA, anti-microbial antibodies were exclusively seen in untreated CD; however, the overall sensitivity was low. Any glycan positivity (LR+: 3.13; 95% CI: 2.08-4.73) was associated with an increased likelihood ratio for diagnosing CD. Significant correlation was found between the levels of anti-glycan and anti-endomysial or anti-transglutaminase antibodies. Anti-glycan positivity was lost after longstanding GFD. Anti-glycan antibody titers were associated with symptoms at presentation, but not the presence of NOD2/CARD15 mutations. Patients with severe malabsorption more frequently had multiple antibodies at diagnosis (P = 0.019)., Conclusion: The presence of anti-glycan antibodies in CD seems to be secondary to the impaired small bowel mucosa which can lead to increased antigen presentation. Furthermore, anti-glycan positivity may be considered an additional marker of CD and dietary adherence.

It has been suggested that human herpesvirus 8 (HHV-8), also known as KSHV (Kaposi's sarcoma-associated human herpesvirus), might possess a promoting effect in the development and progression of monoclonal gammopathies. In this study, the presence of Epstein-Barr virus (EBV), human cytomegalovirus (CMV), human herpesvirus 6 (HHV-6) and human herpesvirus 8 (HHV-8) were tested in patients with multiple myeloma (MM) using both serologic and nucleic acid amplification techniques. The transient reactivation or continuous presence of EBV, CMV, HHV-6 and HHV-8 could be detected in, respectively, 36, eight, 13 and 29 of 69 MM patients; nine, one, four and six of 16 monoclonal gammopathy of unknown significance patients; and seven, four, zero and five of 10 Waldenström's macroglobulinemia patients. The total number of MM patients was 95. HHV-8 PCR-positivity was significantly more frequent in the MM group than in the control group of patients with non-Hodgkin's lymphoma (NHL). However, serologic testing did not reveal significant differences between the two patient groups. The number of MM patients with concomitant herpesvirus infections as detected by PCR was as follows: 15 double, seven triple and two quadruple virus nucleic acid positive. In 13/95 MM patients, the simultaneous presence of acute EBV infection and HHV-8 PCR-positivity was detected compared with none of the control group (P=0.009). These results indicate that in addition to HHV-8, the transitional reactivation of EBV may also play a role in the pathogenesis of MM.

The genotype and phenotype characteristics of Hungarian patients with RET proto-oncogene mutations operated on for hereditary medullary thyroid cancer (MTC) were studied. The genetic screening was performed in two centers and 40 patients with hereditary MTC or C-cell hyperplasia (CCH) from 18 unrelated families were analyzed. One patient having a mutation in exon 16 (Met918Thr) presented with the MEN2B phenotype, six patients from two families had hereditary MTC without pheochromocytoma (pheo) and primary hyperparathyroidism (PHPT), whereas 33 patients from 15 families showed the MEN2A phenotype. Two different mutations were identified in exon 10 (Cys609Tyr and Cys609Ser), five different mutations were present in exon 11 (Cys634Phe, Cys634Arg, Cys634Tyr, Cys634Trp and Cys634Ser), and two different mutations were localized in exon 14 (Val804Met and Val804Leu). Mutations in exon 10 were associated with hereditary MTC (Cys609Tyr) or with MEN2A syndrome (Cys609Ser). Mutations in exon 11 were always associated with the MEN2A phenotype. PHPT was present in one patient with mutation in exon 14 (Val804Met), whereas all other patients affected with mutations in exon 14 had hereditary MTC without PHPT and/or pheos.

The most common form of non-syndromic autosomal recessive deafness (NSRD) is caused by mutations in the gene GJB2, encoding the protein connexin 26 (Cx26). The mutation c.35delG is found in 30-70% of Caucasian NSRD cases, and is abundant (allele frequency of 0.5-2%) in several European populations, while c.167delT is found in the Ashkenazi Jewish population with about 2% frequency. In the current study, using simple PCR-based tests we established an allele frequency of 0.6% in the Hungarian average, and 0.4% in the Romani (Gypsy) populations for the c.35delG mutation, and an allele frequency of 2.4% in the Ashkenazi population for the c.167delT mutation. Our results do not differ significantly from the published data for Caucasian and non-European Ashkenazi populations and they present figures for the Romani population for the first time. Both mutations may be significant causative factors among the NSRD cases of the respective populations in Central Europe.

Hereditary angioneurotic edema (HAE) is an autosomal dominant disorder characterized by episodic local subcutaneous and submucosal edema caused by the deficiency of activated C1 esterase inhibitor protein (C1-INH, type I (C1NH): reduced serum antigen level, type II: reduced activity and normal serum antigen level). The aim of the present study was to determine the disease-causing mutations in the C1INH gene (SERPING1) among Hungarian HAE-patients. The estimated number of affected HAE-families in Hungary is 40-50, out of which 26 families (type I:23, type II:3) managed in a single center were enrolled in the current study. To detect large deletions/insertions, we used Southern-blotting analysis followed by real time PCR based gene dosage analysis. In the absence of large structural changes, we employed direct sequencing covering the whole coding region and splicing sites of the C1INH gene. Large deletions were detected in 4/23 (17.4%) type I families. We found the g.16788C>T (p.Arg444Cys) mutation in each 3, type II HAE-families. In the remaining type I families, 13 previously unreported mutations (g.638G>A, g.2238C>T, g.2534&#95;2535delCT, g.2579&#95;2620del42, g.2533G>A, g.2695G>A, g.2696&#95;2697insT, g.4467C>T, g.14224A>T, g.14107delA, g.16749&#95;;16775dup, g.16810T>A, g.16885C>G) were detected in 16 families affecting primarily exon 3 (6/13) of the C1INH gene. In the 3 remaining families, known mutations were identified affecting primarily exon 8 (2/3)., (Copyright 2003 Wiley-Liss, Inc.)

Genotypic testing of nonselected patients with the myelodysplastic syndrome (MDS) for the C282Y and H63D mutations of the HFE gene responsible for hereditary hemochromatosis revealed a significantly increased frequency of these mutations when compared to healthy blood donors reflecting the average population. Among the 50 patients examined [26 refractory anemia (RA), 9 refractory anemia with ring sideroblasts (RARS), 2 refractory anemia with excess of blasts (RAEB) and 13 refractory anemia with excess of blasts in transformation (RAEB-t)] there were 24 heterozygotes (20 for H63D and 4 for C282Y), 1 homozygote for H63D and 1 compound heterozygote. The difference between the HFE-positive and HFE-negative MDS patients as regards initial serum iron and transferrin saturation was not significant. Inevitably the iron overload syndrome eventually develops in MDS patients due to intrinsic characteristics of the disease as well as an escalating need for blood transfusion therapy in the course of the disease. The high incidence rate of HFE gene mutations among MDS patients may also contribute to this vicious circle., (Copyright 2003 S. Karger AG, Basel)

Galactokinase deficiency is an inborn error of metabolism that, if untreated, results in the development of cataracts in the first weeks of life. The disorder is rare worldwide, but has a high incidence among the Roma (Gypsies). In 1999, we reported the founder Romani mutation, P28T, identified in affected families from Bulgaria. Subsequent studies have detected the same mutation in Romani patients from different European countries. The screening of 803 unrelated control individuals of Romani ethnicity from Bulgaria, Hungary, and Spain has shown an overall carrier rate of 1:47 and an expected incidence of affected births about 1:10,000. Using disease haplotype analysis, the age of the P28T mutation was estimated at 750 y, preceding the splits of the proto-Roma into the numerous populations resident in Europe today. The findings suggest that the mutation has spread with the early diaspora of the Roma throughout Europe. Superimposed on this old distribution pattern is the new migration wave of the last decade, with large numbers of Roma moving to Western Europe as a result of the economic changes in the East and the wars in former Yugoslavia. The changing demographic pattern of Romani minorities can be expected to lead to a homogenization of the incidence of "private" Romani disorders and founder mutations. The P28T mutation is thus likely to account for a high proportion of galactokinase deficiency cases across Europe. Mutation-based pilot newborn screening programs would provide current incidence figures and help to design long-term prevention of infantile cataracts due to galactokinase deficiency.

Background and Purpose: The classical risk factors did not explain all the possible etiology of cerebral stroke. Genetic polymorphisms responsible for thrombophilia were implicated recently as risk factors of stroke. In this genetico-epidemiological study the author's aim was to analyse the tendency of genetic polymorphisms to cluster in a cohort of young and elderly stroke patients and in healthy subjects in Hungary., Methods: 253 patients with stroke were compared with 173 healthy blood donors on the basis of genetic polymorphisms of platelet GP IIb/IIIa receptor (33 LeuPro), prothrombin gene G20210A, Factor V Leiden mutation, ACE I/D, methylenetetrahydrofolate reductase (MTHFR) and beta fibrinogen gene G455A. These data were acquired using PCR. Questionnaires were used to investigate the family history and to determine the risk factor profile. The subtypes of stroke were analysed in a stroke cohort grouped according to different polymorphisms., Results: An increased frequency of GP IIIa heterozygosity was found as compared to a West-European stroke cohort (31% versus 19%). The prothrombin gene variant (2.9% European and 4.8% in Hungary) was also found to increase in frequency. In young stroke patients (age < 50) compared with control subjects the odds ratios were higher: in prothrombin gene (OR: 4.9), in Leiden mutation (OR: 1.67), in fibrinogen gene (OR: 1.64) and in MTHFR(+/+) (OR: 1.58). Clustering of two polymorphisms could only be detected in young patients. These clustering polymorphisms were GP IIb/IIIa with prothrombin G20210A variant (OR: 6.74, 95% CI 1.1-18.2) and prothrombin gene variant with MTHFR (OR: 5.3, CI95 1.2-8.3)., Conclusion: Selected and clustered genetic polymorphisms of haemostatic factors could be responsible for the high stroke morbidity in Central Europe. The presence and clustering tendency of these factors have been described in young stroke victims.

Hereditary hemochromatosis is an autosomal, recessive disorder of the iron metabolism. The hemochromatosis gene (HFE) was previously located on chromosome 6 and recently identified by positional cloning. A point mutation, C282Y, was found to be present in the HFE gene in homozygous form in 64 to 100% of patients with established hemochromatosis. The relationship of a second polymorphic variant of the HFE gene, H63D to the formation of iron overload is debated. Although hemochromatosis is one of the most common inherited disorders among Caucasians, in the absence of specific signs it is rarely diagnosed. In order to obtain comparable epidemiological data for Hungary, we tested 1271 and 277 randomly selected, unrelated, healthy subjects for C282Y and H63D respectively. In addition C282Y testing was carried out in 58 patients suffering from liver cirrhosis, and in 191 individuals with suspected hemochromatosis. For C282Y and H63D mutation analyses polymerase chain reaction technique followed by Rsa I and Bcl I restriction enzyme digestion was used. We developed an alternative method for the detection of C282Y based on an amplification-generated Kpn I restriction site. The allele frequencies were 3.8% and 12.3% for C282Y and H63D respectively in the normal Hungarian population. There was no significant difference in C282Y allele frequencies between liver disease patients (1.7%) and the normal population. We identified 15 homozygous and 25 heterozygous individuals among 191 individuals with suspected hemochromatosis. The C282Y and the H63D allele frequencies in the normal Hungarian population were found to be similar to the allele frequencies observed in other European populations, indicating that there is a large number of individuals susceptible for iron overload in Hungary (1:700). Mutation analysis is a novel, non-invasive method in the diagnostics of hereditary hemochromatosis, which increasingly becomes part of the routine clinical work.

In haemophilia A (HA), besides the direct detection of the most common mutation of the factor VIII gene (the gene inversion), it was necessary to establish indirect methods which are suitable to reveal the pattern of inheritance of the genes examined, regardless of the mutations they carry. This task can be achieved by the analysis of DNA polymorphisms located within and in the near proximity of the factor VIII gene. For diagnostic purposes we used an RFLP and two microsatellite polymorphisms. The aim of our program is to provide carrier and also prenatal diagnostics for affected families. So far we completed the analyses of 15 HA patients and 68 of their family members, and we gave prenatal diagnoses in 3 cases. According to the information content of the polymorphisms used, we expect to be able to provide DNA diagnoses to 95% of the Hungarian HA families requesting the test.