The Undiagnosed Diseases Network International: Five years and more!

Undiagnosed rare diseases (URDs) account for a significant portion of the overall rare disease burden, depending upon the country. Hence, URDs represent an unmet medical need. A specific challenge posed by the ensemble of the URD patient cohort is the heterogeneity of its composition; the group, indeed, includes very rare, still unidentified conditions as well as clinical variants of recognized rare diseases. Exact disease recognition requires new approaches that cut across national and institutional boundaries, may need the implementation of methods new to diagnostics, and embrace clinical care and research. To address these issues, the Undiagnosed Diseases Network International (UDNI) was established in 2014, with the major aims of providing diagnoses to patients, implementing additional diagnostic tools, and fostering research on novel diseases, their mechanisms, and their pathways. The UDNI involves centres with internationally recognized expertise, and its scientific resources and know-how aim to fill the knowledge gaps that impede diagnosis, in particularly for ultra-rare diseases. Consequently, the UDNI fosters the translation of research into medical practice, aided by active patient involvement. The goals of the UDNI are to work collaboratively and at an international scale to: 1) provide diagnoses for individuals who have conditions that have eluded diagnosis by clinical experts; 2) gain insights into the etiology and pathogenesis of novel diseases; 3) contribute to standards of diagnosing unsolved patients; and 4) share the results of UDNI research in a timely manner and as broadly as possible.

Atypical neurofibromatosis type 1 with unilateral limb hypertrophy mimicking overgrowth syndrome.

Neurofibromatosis type 1 (NF1; OMIM 162200), a dominantly inherited multitumor syndrome, results from mutations in the Neurofibromin 1 (NF1) gene. We present the case of a Hungarian woman with the clinical phenotype of NF1 over her whole body and the clinical features of unilateral overgrowth involving her entire left leg. This unusual phenotype suggested either the atypical form of NF1 or the coexistence of NF1 and overgrowth syndrome. Direct sequencing of the genomic DNA isolated from peripheral blood revealed a novel frameshift mutation (c.5727insT, p.V1909fsX1912) in the NF1 gene. Next-generation sequencing of 50 oncogenes and tumour suppressor genes, performed on the genomic DNAs isolated from tissue samples and peripheral blood, detected only wild-type sequences. Based on these results, we concluded that the patient is affected by an unusual phenotype of NF1, and that the observed unilateral overgrowth of the left leg might be a rare consequence of the identified c.5727insT mutation.

Involvement of the cholinergic basal forebrain nuclei in spinocerebellar ataxia type 2 (SCA2).

AIMS: Spinocerebellar ataxia type 2 (SCA2) belongs to the CAG repeat or polyglutamine diseases. Along with a large variety of motor, behavioural and neuropsychological symptoms the clinical picture of patients suffering from this autosomal dominantly inherited ataxia may also include deficits of attention, impairments of memory, as well as frontal-executive and visuospatial dysfunctions. As the possible morphological correlates of these cognitive SCA2 deficits are unclear we examined the cholinergic basal forebrain nuclei, which are believed to be crucial for several aspects of normal cognition and may contribute to impairments of cognitive functions under pathological conditions. METHODS: We studied pigment-Nissl-stained thick tissue sections through the cholinergic basal forebrain nuclei (that is, medial septal nucleus, nuclei of the diagonal band of Broca, basal nucleus of Meynert) of four clinically diagnosed and genetically confirmed SCA2 patients and of 13 control individuals according to the pathoanatomical approach. The pathoanatomical results were confirmed by additional quantitative investigations of these nuclei in the SCA2 patients and four age- and gender-matched controls. RESULTS: Our study revealed a severe and consistent neuronal loss in all of the cholinergic basal forebrain nuclei (medial septal nucleus: 72%; vertical nucleus of the diagonal band of Broca: 74%; horizontal limb of the diagonal band of Broca: 72%; basal nucleus of Meynert: 86%) of the SCA2 patients studied. Damage to the basal forebrain nuclei was associated with everyday relevant cognitive deficits only in our SCA2 patient with an additional Braak and Braak stage V Alzheimer's disease (AD)-related tau pathology. CONCLUSIONS: The findings of the present study: (1) indicate that the mutation and pathological process underlying SCA2 play a causative role for this severe degeneration of the cholinergic basal forebrain nuclei and (2) may suggest that degeneration of the cholinergic basal forebrain nuclei per se is not sufficient to cause profound and global dementia detrimental to everyday practice and activities of daily living.

Inventory of Non-Ataxia Signs (INAS): validation of a new clinical assessment instrument.

Although ataxia is by definition the prominent symptom of ataxia disorders, there are various neurological signs that may accompany ataxia in affected patients. Reliable and quantitative assessment of these signs is important because they contribute to disability, but may also interfere with ataxia. Therefore we devised the Inventory of Non-Ataxia Signs (INAS), a list of neurological signs that allows determining the presence and severity of non-ataxia signs in a standardized way. INAS underwent a rigorous validation procedure that involved a trial of 140 patients with spinocerebellar ataxia (SCA) for testing of inter-rater reliability and another trial of 28 SCA patients to assess short-term intra-rater reliability. In addition, data of the ongoing EUROSCA natural history study were used to determine the reproducibility, responsiveness and validity of INAS. Inter-rater reliability and short-term test-retest reliability was high, both for the total count and for most of the items. However, measures of responsiveness, such as the smallest detectable change and the clinically important change were not satisfactory. In addition, INAS did not differentiate between subjects that were subjectively stable and those that worsened in the 2-year observation period. In summary, INAS and INAS count showed good reproducibility, but unsatisfactory responsiveness. The present analysis and published data from the EUROSCA natural history study suggest that INAS is a valid measure of extracerebellar involvement in progressive ataxia disorders. As such, it is useful as a supplement to the measures of ataxia, but not as a primary outcome measure in future interventional trials.

Prospective analysis of falls in dominant ataxias.

In a previous retrospective study, we demonstrated that falls are common and often injurious in dominant spinocerebellar ataxias (SCAs) and that nonataxia features play an important role in these falls. Retrospective surveys are plagued by recall bias for the presence and details of prior falls. We therefore sought to corroborate and extend these retrospective findings by means of a prospective extension of this fall study. 113 patients with SCA1, SCA2, SCA3 or SCA6, recruited from the EuroSCA natural history study, were asked to keep a fall diary in between their annual visits to the participating centres. Additionally, patients completed a detailed questionnaire about the first three falls, to identify specific fall circumstances. Relevant disease characteristics were retrieved from the EuroSCA registry. 84.1% of patients reported at least one fall during a time period of 12 months. Fall-related injuries were common and their frequency increased with that of falls. The presence of nonataxia symptoms was associated with a higher fall frequency. This study confirms that falls are a frequent and serious complication of SCA, and that the presence of nonataxia symptoms is an important etiological factor in its occurrence.

Mutations of the apolipoprotein A5 gene with inherited hypertriglyceridaemia: review of the current literature.

Apoliporotein A5 (APOA5), a member of the apolipoprotein family, plays a key regulatory role in triglyceride (TG) metabolism. Even though the exact biochemical background of its mechanism is not yet fully understood, diseases associated with this particular gene highlighted its key role in the metabolism of triglycerides in humans. Naturally occurring functional variants of the gene and their natural major haplotypes are known to associate with moderately elevated triglyceride levels, and are also known to confer risk or protection for major polygenic diseases, like coronary heart disease, stroke, or metabolic syndrome. On the other hand, case reports and even robust resequencing studies verified APOA5 mutations as underlying genetic defects behind extreme hypertriglyceridemic phenotype. Soon after the recognition of the first cases, there were indications which suggest the existence of less frequent genetic variants which, in combination with the common allelic variants of the gene, can define haplotypes that are associated with substantial triglyceride level increase. In addition, it became evident, that there are rare mutations of the APOA5 gene which can be associated with specific complex phenotypes and different types of hyperlipoproteinemia, which includes extremely high triglyceride levels with multiple organ pathology. These rare mutations may cause inheritable hypertriglyceridemia, but they presented at a low frequency and could not be captured by standard genotyping array screenings. The identification of new mutations still relies on the direct sequencing of APOA5 gene of patients with hypertriglyceridemia with an unusual pattern, individually or in huge resequencing studies.

Investigation of JAK2, STAT3 and CCR6 polymorphisms and their gene-gene interactions in inflammatory bowel disease.

Genome-wide association studies identified many loci associated with the two forms of inflammatory bowel disease (IBD), Crohn's disease (CD) and ulcerative colitis (UC). Components of the interleukin-23 signalling pathway, such as IL23R, JAK2 and STAT3, have been implicated in both diseases. In addition, emerging evidence supports the role of IL23-driven Th17 cells in inflammation. Here, we studied the susceptibility nature of three components of IL23 signalling and Th17 cell differentiation: JAK2 rs10758669, STAT3 rs744166 and CCR6 rs2301436 initially associated with CD in Hungarian CD and UC patients. A total of 616 unrelated subjects with either form of IBD and 496 healthy controls were genotyped with PCR-RFLP methods. We also tested the genetic interactions of JAK2, STAT3 and CCR6 polymorphisms in a pairwise fashion with regard to disease risk. We could confirm the susceptibility of STAT3 rs744166 TT homozygotes for UC (OR: 1.483, 95% CI: 1.103-1.992, P = 0.009). Data on genetic interaction reveals that the above JAK2 and STAT3 risk alleles contribute to CD susceptibility in combination with each other (OR: 2.218; 95% CI: 1.097-4.487; P = 0.024), while the JAK2 variant shows a tendency to confer UC risk only on a wild-type STAT3 background (OR: 1.997, 95%CI: 0.994-4.009, P = 0.049). Our results may help in understanding how these natural variants contribute to development of IBD through their genetic association.

The natural history of spinocerebellar ataxia type 1, 2, 3, and 6: a 2-year follow-up study.

OBJECTIVE: To obtain quantitative data on the progression of the most common spinocerebellar ataxias (SCAs) and identify factors that influence their progression, we initiated the EUROSCA natural history study, a multicentric longitudinal cohort study of 526 patients with SCA1, SCA2, SCA3, or SCA6. We report the results of the 1- and 2-year follow-up visits. METHODS: As the primary outcome measure we used the Scale for the Assessment and Rating of Ataxia (SARA, 0-40), and as a secondary measure the Inventory of Non-Ataxia Symptoms (INAS, 0-16) count. RESULTS: The annual increase of the SARA score was greatest in SCA1 (2.18 ± 0.17, mean ± SE) followed by SCA3 (1.61 ± 0.12) and SCA2 (1.40 ± 0.11). SARA progression in SCA6 was slowest and nonlinear (first year: 0.35 ± 0.34, second year: 1.44 ± 0.34). Analysis of the INAS count yielded similar results. Larger expanded repeats and earlier age at onset were associated with faster SARA progression in SCA1 and SCA2. In SCA1, repeat length of the expanded allele had a similar effect on INAS progression. In SCA3, SARA progression was influenced by the disease duration at inclusion, and INAS progression was faster in females. CONCLUSIONS: Our study gives a comprehensive quantitative account of disease progression in SCA1, SCA2, SCA3, and SCA6 and identifies factors that specifically affect disease progression.

Monitoring of group A rotaviruses in wild-living birds in Hungary.

Rotavirus is a common pathogen causing gastroenteritis in humans and domesticated animals. The incidence of rotavirus in wild-living animals, particularly in avian species, has not been systematically investigated. In this study 1220 fecal samples and cloacal swabs collected from wild-living birds during 2008 in Hungary were tested for the presence of group A rotaviruses by a VP6 gene-specific reverse-transcription-polymerase-chain-reaction assay. Of the 1220 samples, 276 and 944 were processed as individual and pooled specimens, respectively. Rotavirus was identified in two pooled pheasant (Phasianus colchicus) samples and two individual reed bunting samples (Emberiza schoeniclus). These data indicated a very low prevalence of group A rotaviruses (0.3%) in our sample set. Nonetheless, the present study, together with existing literature data, implies that rotavirus infections occur in a wide spectrum of feral bird species. These findings are exciting and suggest that pursuing rotavirus monitoring is needed to uncover avian rotavirus strain diversity and understand rotavirus ecology in nature.

Functional glucokinase regulator gene variants have inverse effects on triglyceride and glucose levels, and decrease the risk of obesity in children.

OBJECTIVE: Recently, the association of the natural variants rs1260326 and rs780094 of the glucokinase regulatory protein (GCKR) gene with increased fasting triglycerides and decreased fasting plasma glucose in diabetic adults was reported; the minor alleles were also found to reduce the risk of type 2 diabetes. The present study examined the possible associations of these variants with triglycerides and glucose levels, their allele distribution and their possible effects on childhood obesity. METHODS AND RESULTS: A total of 221 obese children and 115 healthy normal-weight children as controls were genotyped using PCR-RFLP methods. Both functional GCKR variants were found in association with elevated serum triglycerides and lower fasting plasma glucose levels. Results of logistic regression revealed that, despite higher triglyceride levels, the carriers of the GCKR variants were more protected against the development of obesity; the adjusted models confirmed the lower risk of obesity for both variants (rs1260326: OR, 0.46; 95% CI, 0.25-0.83; rs780094: OR, 0.41; 95% CI, 0.23-0.74). CONCLUSION: Our findings confirm the inverse modulating effect of functional GCKR variants on triglycerides and glucose levels in obese paediatric patients and healthy normal-weight controls. The results of our study strongly suggest that the minor alleles confer protection against the development of obesity in children. The findings also suggest that the minor alleles of functional GCKR may protect against diabetes and the metabolic syndrome in adults.

Triglyceride level affecting shared susceptibility genes in metabolic syndrome and coronary artery disease.

Metabolic syndrome is characterized primarily by abdominal obesity, high triglyceride- and low HDL cholesterol levels, elevated blood pressure, and increased fasting glucose levels, which are often associated with coronary heart diseases. Several factors, such as physical inactivity, age, and several endocrine and genetic factors can increase the risk of the development of the disease. Gathered evidence shows, that metabolic syndrome is not only a risk factor for cardiovascular disease, but often both of them have the same shared susceptibility genes, as several genetic variants have shown a predisposition to both diseases. Due to the spread of robust genome wide association studies, the number of candidate genes in metabolic syndrome and coronary heart disease susceptibility increases very rapidly. From the growing spectrum of the genes influencing lipid metabolism (like the LPL; PPARA; APOE; APOAI/CIII/AIV genecluster and APOAS5), the current review focuses on shared susceptibility variants involved in triglyceride metabolism and consequently the effects on the circulating triglyceride levels. As the elevated levels of triglycerides can be associated with disease phenotypes, some of these SNPs can have susceptibility features in both metabolic syndrome and in coronary heart disease, thereby some of them can even represent a kind of susceptibility link between metabolic syndrome and coronary artery disease.

L-carnitine supplementation and adipokines in patients with end-stage renal disease on regular hemodialysis.

Chronic hemodialysis (HD) patients frequently encounter carnitine depletion, elevated adipose tissue-derived hormones/cytokines, that may contribute to accelerated arteriosclerosis. 10 non-diabetic HD patients were studied over 28 weeks. In the 12 weeks treatment period 1 g L-carnitine was given iv after each HD session. Measurements of plasma free- and acylcarnitines, insulin, leptin, adiponectin, resistin and ghrelin were performed at baseline, at weeks 2, 4, 8, 12 (treatment period) and at weeks 24-28 (post-treatment period). L-carnitine supplementation resulted in progressive increase of free- and acylcarnitine levels. Plasma levels of insulin, resistin, leptin and ghrelin remained at the already elevated baseline values. L-carnitine therapy induced a significant increase in plasma adiponectin from 20.2 ± 12.7 µg/ml (baseline) to 32.7 ± 20.2 µg/ml in week 2 (p<0.05) and 35.4 ± 19.6 µg/ml in week 12 (p < 0.03), which remained unchanged in the post-carnitine period. Plasma insulin levels correlated positively with leptin (r = 0.525, p<0.0001) and resistin (r = 0.284, p<0.005); adiponectin levels correlated inversely with leptin (r = -0.255, p<0.02) and resistin (r = -0.213, p<0.04) irrespective of carnitine status. Plasma levels of adipokines and related hormones are greatly elevated in patients on regular HD. L-carnitine administration further augmented the plasma levels of protective adiponectin, therefore it may have a role in preventing cardiovascular complications of uremia.

Responsiveness of different rating instruments in spinocerebellar ataxia patients.

OBJECTIVE: To determine the longitudinal metric properties of recently developed clinical assessment tools in spinocerebellar ataxia (SCA). METHODS: A subset of 171 patients from the EUROSCA natural history study cohort (43 SCA1, 61 SCA2, 37 SCA3, and 30 SCA6) were examined after 1 year of follow-up. Score changes and effect size indices were calculated for clinical scales (Scale for the Assessment and Rating of Ataxia [SARA], Inventory of Non-Ataxia Symptoms [INAS]), functional tests (SCA Functional Index [SCAFI] and components), and a patient-based scale for subjective health status (EQ-5D visual analogue scale [EQVAS]). Responsiveness was determined in relation to the patient's global impression (PGI) of change and reproducibility described as retest reliability for the stable groups and smallest detectable change. RESULTS: Within the 1-year follow-up period, SARA, INAS, and SCAFI but not EQVAS indicated worsening in the whole group and in the groups with subjective (PGI) worsening. SCAFI and its 9-hole pegboard (9HPT) component also deteriorated in the stable groups. Standardized response means were highest for 9HPT (-0.67), SARA (0.50), and SCAFI (-0.48) with accordingly lower sample size estimates of 143, 250, or 275 per group for a 2-arm interventional trial that aims to reduce disease progression by 50%. SARA and EQVAS performed best to distinguish groups classified as worse by PGI. All scales except EQVAS reached the criterion for retest reliability. CONCLUSION: While both the Scale for the Assessment and Rating of Ataxia and the SCA Functional Index (SCAFI) (and its 9-hole pegboard component) had favorable measurement precision, the clinical relevance of SCAFI and 9-hole pegboard score changes warrants further exploration. The EQ-5D visual analogue scale proved insufficient for longitudinal assessment, but validly reflected patients' impression of change.

Triglyceride level modifying functional variants of GALTN2 and MLXIPL in patients with ischaemic stroke.

BACKGROUND: Recent genome-wide studies identified several genetic variants associated with blood lipid level alterations. Because affected lipid metabolism can confer risk to the development of ischaemic stroke, we studied three polymorphisms reportedly associated with triglyceride-level changes, rs17145738 and rs3812316 of the MLXIPL locus, and rs4846914 variant of GALNT2 gene in biobanked samples of patients with stroke. This pool of samples was previously investigated for haplotype tagging minor alleles of apolipoprotein A5 gene (T-1131C, T1259C, IVS3+G476A and C56G), and an association was found between the minor allele carriage and the triglyceride levels, and also these variants were found to confer risk to the development of stroke. METHODS: Here, a total of 467 patients with stroke, stratified as large vessel, small vessel and mixed stroke groups, and 156 control subjects were genotyped using PCR-RFLP methods. RESULTS: In the current study, we could not verify association of the variants analyzed either with triglyceride and total cholesterol levels or with the risk of ischaemic stroke susceptibility. CONCLUSIONS: The data presented here revealed differentiated risk nature of the triglyceride level modifying natural gene variants.

A polymorphism within the fructosamine-3-kinase gene is associated with HbA1c Levels and the onset of type 2 diabetes mellitus.

BACKGROUND: Non-enzymatic glycation is a process, which leads to the formation of advanced glycation endproducts. These compounds are involved in the development of diabetic microvascular complications. Fructosamine-3-kinase (FN3K) is an intracellular enzyme that phosphorylates fructosamines resulting in fructosamine-3-phosphate, which subsequently decomposes to inorganic phosphate, 3-deoxyglucasone and the unmodified amine. Recently, the G900C (rs1056534) single nucleotide polymorpism (SNP) of the FN3K gene was found to be associated with the enzyme activity. OBJECTIVE/DESIGN: The aim of the study was to investigate the impact of the SNP on clinical and biochemical features and microvascular complications of type 2 diabetes. PATIENTS: A total of 859 type 2 diabetic subjects and 265 healthy controls were enrolled in the study and were genotyped with PCR-RFLP method. RESULTS: Genotype frequencies were as follows, CC: 5%, GC: 54%, GG: 41% in subjects with type 2 diabetes and CC: 6%, GC: 51%, GG: 43% in the controls. Diabetic subjects with the CC variant had lower HbA (1c) levels compared with the others (CC: 6.48+/-0.05%; GC: 7.66+/-0.09%; GG: 7.68+/-0.09%; p<0.001). Furthermore, in case of the CC allelic variant type 2 diabetes was diagnosed at a later age than in case of GC or GG variants (CC: 56.0+/-1.90 years; GC: 52.0+/-0.62 years; GG: 50.1+/-0.71 years; p<0.05). Logistic regression analysis did not reveal association between CC genotype and diabetic complications, such as diabetic nephropathy, neuropathy and retinopathy (OR=1.036, CI 95% 0.652-1.647, p=0.880; OR=0.985, CI 95% 0.564-1.721 p=0.958; OR=1.213, CI 95% 0.470-3.132, p=0.690, respectively). CONCLUSION: We conclude that the G900C polymorphism associates with the level of HbA (1c) and the onset of the disease, but not with either of the diabetic microvascular complications.

Haplotype analysis of the apolipoprotein A5 gene in patients with the metabolic syndrome.

BACKGROUND AND AIMS: In recent studies, the T-1131C variant of apolipoprotein A5 (APOA5) gene was found to confer a risk for metabolic syndrome (MS). Here we determined four haplotype-tagging polymorphisms (T-1131C, IVS3+G476A, T1259C, and C56G), and studied the distribution of the naturally occurring major haplotype profiles in MS. METHODS AND RESULTS: A total of 343 MS patients and 284 controls were genotyped using PCR-RFLP methods. Both in MS and control groups, we confirmed the already known association of -1131C, IVS3+473A and 1259C minor alleles with elevated triglyceride levels. The prevalence of the APOA5*2 haplotype (the combination of T-1131C, IVS3+G476A and T1259C SNPs) was 13.1% in MS patients, and 4.9% in controls (p<0.001); multiple logistic regression analysis revealed that this haplotype confers risk for the development of MS (OR=2.880; 95% CI: 1.567-5.292; p=0.001). We also observed a gender effect: in males a more prominent degree of susceptibility was found. Contrary to the APOA5*2 haplotype, the prevalence rate of APOA5*4 (determined by the T-1131C SNP alone) did not differ between MS patients and controls. We identified a novel haplotype, designated here as APOA5*5 (1259C allele alone); which appears to be protective against MS. CONCLUSION: Our results refined the role of SNP T-1131C in the development of MS. The susceptibility nature of this SNP is limited to the APOA5*2 haplotype, while in APOA5*4 haplotype it did not confer a risk for the disease. In addition, as our current data suggest, the novel APOA5*5 haplotype can confer protection against MS.

Plasma carnitine ester profiles in Crohn's disease and ulcerative colitis patients with different IGR2230a_1 genotypes.

An association has been repeatedly demonstrated between inflammatory bowel disease (IBD) and the IBD5 locus in the 5q31 chromosomal region. The aim of the present study was to examine the prevalence of the IGR2230a_1 intronic nucleotide polymorphism of the slc22a5 gene (coding for the OCTN2 carnitine transporter protein) lying within this region, and its possible relationship with the carnitine metabolism in Hungarian IBD patients and controls. We genotyped by restriction fragment length polymorphism 200 Crohn's disease (CD) and 246 ulcerative colitis (UC) patients, as well as 187 healthy controls. From plasma samples we determined detailed carnitine ester profiles of 76 CD, 43 UC patients and 45 control persons using electrospray ionization triple quadruple tandem mass spectrometry. The distribution of the genotypes was not significantly different in the CD or the UC group compared with the controls. We found no significant alterations of the carnitine profile in the carrier/non-carrier or the homozygote/non-homozygote comparisons in both the CD and the UC groups, stratified by IGR2230a_1 genotype. Our data suggest that this polymorphism alone is not associated with CD and UC in the Hungarian population, and has no effect on the carnitine metabolism.

Functional variants of the interleukin-23 receptor gene in non-gastrointestinal autoimmune diseases.

Variants of the gene of the interleukin-23 receptor (IL23R) were first identified as susceptibility factors in association with inflammatory bowel diseases. Since then it became clear that different variants of the gene play also role in a number of other autoimmune diseases like psoriasis, rheumatoid arthritis, ankylosing spondylitis and multiple sclerosis while in others, like systemic sclerosis, systemic lupus erythematosus or Sjögren syndrome the same effect could not be seen. However, the results are very controversial both in terms of the various polymorphisms and also in population specificity. The aim of the current paper is to overview all available reports on IL23R gene polymorphisms in various autoimmune and inflammatory diseases and to try to give an explanation on the possible effect of the examined variants.

Variants of the IL23R gene are associated with ankylosing spondylitis but not with Sjögren syndrome in Hungarian population samples.

Recently, associations were found between several autoimmune diseases and functional variants of interleukin-23 receptor (IL23R) gene; here, we studied the possible association of nine polymorphisms of IL23R with ankylosing spondylitis (AS) and with Sjögren syndrome (SS). In our study, we genotyped groups of patients with AS (n = 206), SS (n = 156) and healthy controls (n = 235) for rs11805303, rs10889677, rs1004819, rs2201841, rs11209032, rs11209026, rs10489629, rs7517847 and rs7530511 variants using PCR-RFLP methods. We observed significant increase in the carriage of the T allele of rs11805303 and the A allele of rs1004189 in the AS group compared with the controls. For the rs10889677 variant, the prevalence of the AA genotype and for the rs2201841, the CC genotype showed a more than two-fold increase in the AS group compared with the controls. By contrast, the GA heterozygous genotype of rs11209026 variant showed a significant decrease in AS patients compared with controls. Haplotype analysis revealed association of four IL23R haplotypes with AS. There was no difference in the distribution of any of the examined IL23R variants between controls and SS patients. In conclusion, we confirmed the susceptibility or protective associations of IL23R polymorphisms with AS in a Hungarian population and first demonstrated the involvement of the rs11805303 intronic single nucleotide polymorphisms, which was tested so far only for other autoimmune diseases.

Adenovirus gastroenteritis in Hungary, 2003-2006.

The incidence and type distribution of enteric human adenoviruses (HAds) among diarrheic children in south-western Hungary was investigated from 2003 through 2006. Laboratory studies were conducted using commercial antigen detection tests (latex agglutination or immunochromatography), polymerase chain reaction (PCR) amplification, single-strand conformation polymorphism, and sequencing and phylogenetic analysis of a conservative region of the HAd hexon gene. The overall rate of HAd infection in childhood gastroenteritis cases during the 4-year study was 8.1%, with a gradual decrease in detection rates from 11.7% in 2003 to 5.7% in 2006. Molecular studies of a subset of HAd-positive samples found that enteric HAd type 40 strains were identified only in 2003 and 2004, while HAd type 41 strains were identified throughout the 4-year study. Higher detection rates of non-enteric HAds was documented during the first half of the study period when latex agglutination was used in our laboratory for detection. Our study suggests that the choice of diagnostic method may profoundly influence the epidemiologic picture and disease burden attributed to enteric HAd infections.