Polymorphisms in DNA repair genes and risk of non‐Hodgkin lymphoma in a pooled analysis of three studies

Genetic variations in DNA repair genes are thought to play an important role in the pathogenesis and development of non‐Hodgkin lymphoma (NHL). To further explore this hypothesis, we genotyped 319 tag single nucleotide polymorphisms (SNPs) in 27 DNA repair gene regions in 1946 cases and 1808 controls pooled from three population‐based case‐control studies of NHL in the US and Australia. Relative risks of NHL and NHL subtypes in relation to SNP genotypes were assessed using logistic regression. Associations of gene regions and pathways with NHL or NHL subtypes were explored using the minP and tail‐strength statistics, respectively. Overall, genetic polymorphisms within the DNA repair pathway were associated with NHL (P = 0·005). Similar associations were seen with the double‐strand break repair (P = 0·02) and nucleotide excision repair (P = 0·04) pathways. Five SNPs (BLM rs441399, RAD50 rs2237060, FAM82A2 rs2304583, ERCC3 rs4150506, and XRCC4 rs13178127) were particularly noteworthy because their gene regions were significantly associated with NHL or NHL subtypes (minP ≤ 0·05), or because of high level of statistical significance (P ≤ 0·005) and consistent findings across the three studies. These results support the hypothesis that common genetic polymorphisms in human DNA repair genes may modify the risk of NHL.     

Susceptibility to 6‐MP toxicity conferred by a NUDT15 variant in Japanese children with acute lymphoblastic leukaemia

Genotyping of TPMT prior to 6‐mercaptopurine (6‐MP) administration in acute lymphoblastic leukaemia (ALL) patients has been integrated into clinical practice in some populations of European ancestry. However, the comparable rates of 6‐MP myelotoxicity, but rarity of TPMT variants, in Asians suggest that major determinants have yet to be discovered in this population. We genotyped 92 Japanese paediatric ALL patients for NUDT15 rs116855232, a 6‐MP toxicity‐related locus discovered in Asians. Logistic regression and survival analysis were used to evaluate its association with leucopenia, hepatotoxicity, 6‐MP dose reduction, therapy interruption and event‐free survival. The allele frequency of rs116855232 was 0·16, and leucopenia was more common in carriers of the T allele (odds ratio, 7·20; 95% confidence interval, 2·49–20·80; P = 2·7 × 10^?4). As leucopenia results in 6‐MP dose reduction, we observed average doses during maintenance therapy of 40·7, 29·3 and 8·8 mg/m² for patients with CC, CT and TT genotypes, respectively (P < 0·001). Hepatotoxicity was observed only in CC genotype patients. Event‐free survival did not significantly differ by NUDT15 genotype. rs116855232 is an important determinant of 6‐MP myelotoxicity in Japanese children with ALL and may represent the most robust toxicity‐related locus in Asians to date. Considerations for clinical application may be warranted.     

Thyrotoxic hypokalaemic periodic paralysis in a Turkish population: three new case reports and analysis of the case series

Objective Thyrotoxic hypokalaemic periodic paralysis (THPP) is an uncommon condition with intermittent episodes of muscle weakness and occasionally severe paralysis. THPP is a common complication of hyperthyroidism in Asian populations, and has also been reported in other ethnic groups including Caucasians. This study aimed to conduct an analysis of THPP in a Turkish population, and is to our knowledge the first analysis of a homogeneous Caucasian group. Subjects Forty cases with THPP were identified in the Turkish population. Three out of the 40 were new cases and were assigned as index cases. Two cases were not included in the analysis because of lack of data. Results THPP was diagnosed in 10 cases during the first attack and was observed to have a significant shorter complete recovery time statistically in this group (P < 0·01). The majority of cases were hypokalaemic, while there were two normokalaemic cases. Classification of the cases according to their potassium (K) levels revealed that the group with K levels < 2·5 mEq/l had a statistically longer amelioration time than the group with K levels ≥ 2·5 mEq/l. When the cases were classified according to intravenous or oral application of K, the mean amelioration time was 6·8 ± 3·6 h for the intravenous group and 13·1 ± 7·6 for the oral group. Mean complete recovery times of the groups were 29·4 ± 16·2 h and 52·8 ± 18·0 h, respectively. The intravenous group had a shorter amelioration time and complete recovery time, and both were statistically significant (P < 0·05 for each). Conclusions THPP may be seen among Caucasians. Diagnosing THPP during the first attack might decrease the recovery time. The level of hypokalaemia seems to affect the recovery time and initial low K levels may lead to more deterioration in a patient's health compared with mild or near‐normal levels. Intravenous, rather than oral, application of K may be advantageous for shortening both the amelioration and complete recovery times.     

Role of GABRA2 in moderating subjective responses to alcohol

Background: Human twin studies have shown that certain responses to alcohol, including subjective perceptions, are genetically influenced. Previous studies have provided evidence that a low level of response to alcohol predicts future alcohol use disorders in humans. Recent genetic studies suggest an association between alcohol dependence and genetic variation in the γ‐aminobutyric acid A (GABA_A) receptor α2 subunit gene (GABRA2). Based on a haplotypic association of alcohol dependence with GABRA2, we investigated whether GABRA2 alleles are associated with the subjective responses to clamped alcohol concentration. Methods: One hundred and ten healthy social drinkers (53 men) underwent the alcohol clamp. Fifteen minutes after the start of an intravenous infusion of alcohol, the breath alcohol concentration was clamped at a target of 50 ± 5 mg/dl for 165 minutes. Subjective physiologic responses to alcohol and stimulant and sedative effects of alcohol were measured repeatedly during the alcohol clamp. Because aldehyde dehydrogenase 2 (ALDH2) has been shown to have a great impact on the subjective responses to alcohol, we divided subjects by ALDH2 genotype for further analyses. To examine the role of genetic variation in GABRA2, 7 single nucleotide polymorphisms (SNPs) that were informative in association studies were included as factors in the analysis. Results: Among these 7 SNPs, 3 SNPs (rs279869, rs279858, and rs279837) located in the middle of the GABRA2 gene showed significant associations with subjective effects of alcohol. Subjects with 1 or 2 copies of the more common allele showed greater subjective responses to alcohol than did individuals homozygous for the alcohol dependence–associated allele regardless of ALDH2 genotype. Conclusions: These findings confirm and extend the observation that the GABRA2 alleles affect the subjective responses to alcohol, and suggest that the genetic variations in GABRA2 might play a role in the risk of alcohol use disorders by moderating the subjective effects of alcohol.     

Association study of interleukin-12A gene polymorphisms with Graves' disease in two Chinese populations

Objective Graves’ disease (GD) is a common autoimmune disorder and genetic and environmental factors contributing to its aetiology. The pro‐inflammatory cytokine interleukin‐12 (IL‐12) is believed to be critically involved in the pathogenesis of GD. This study aims to elucidate the effect of IL‐12A gene polymorphisms on GD. Design and methods A case–control association study of five tag single nucleotide polymorphisms (SNPs) (rs2243115, rs2243123, rs583911, rs568408 and rs2243143) within the IL‐12A gene was performed in two independent Chinese cohorts. A pilot cohort conducted in Shanghai consisted of 701 patients and 686 controls and a replicate cohort in Xiamen Island included 378 patients and 312 controls. The five SNPs were genotyped by the SNPstream Genotyping Systems and Taqman PCR method. Results Polymorphism of rs568408, located at the 3′‐UTR region, was found to have a significant association with GD in both the cohorts (P_allele = 2·96 × 10^?7 and P_allele = 0·013 for Shanghai and Xiamen Island cohorts, respectively). Haplotype analysis showed that the haplotype of the five SNPs (TTAAG) was associated with a significant risk of GD in both the cohorts (OR = 2·04 and OR = 1·70 for Shanghai and Xiamen Island cohorts, respectively). Conclusion Our results have established an association between IL‐12A polymorphism and GD susceptibility in the Chinese population.     

Polymorphism of the oestrogen receptor beta gene (ESR2) is associated with susceptibility to Graves' disease

Objective To investigate whether a polymorphism in the ESR2 gene (rs4986938, previously associated with endometriosis, ovulatory dysfunction and premature onset of coronary heart disease) increases the risk of Graves’ disease (GD). Subjects and design A cohort of 375 GD patients (300 females and 75 males) and 1001 individuals representative of the background population of Poland (502 males and 499 females) were genotyped for rs4986938 using allele‐specific polymerase chain reaction (PCR). Results We found an increased frequency of the ESR2 A allele among the patients vs. controls (38·0%vs. 32·7%, OR = 1·26, P = 0·009) that was caused by a co‐dominant (OR = 1·25, P = 0·01, P_{for model fit} = 0·127) or a recessive (OR = 1·67, P = 0·003, P_{for model fit} = 0·554) effect. The association was found in both sexes (OR = 1·21, P = 0·046 and OR = 1·53, P = 0·029, respectively, for co‐dominant and recessive models in females, and OR = 1·44, P = 0·034 and OR = 2·29, P = 0·01, respectively, for the two models in males) and was more pronounced among the DRB1*03‐negative (OR = 1·63, P = 0·0002) than DRB1*03‐positive patients (OR = 1·04, P = 0·822). No other statistically significant associations between the ESR2 genotype and GD subsets were found (age of onset, smoking, clinically evident ophthalmopathy, family history of GD, and PTPN22 and CTLA4 (CT60) genotypes were analysed). Conclusions In a Polish population the ESR2 A allele is associated with GD with a strength comparable to polymorphisms of PTPN22 and CTLA4 CT60 loci (OR ~ 1·7). The association with ESR2 is found in both sexes and may be particularly strong among the DRB1*03‐negative individuals.     

rs2072135, a low‐penetrance variant for chronic lymphocytic leukaemia?

Recent multi‐stage genome‐wide association studies (GWAS) have identified single nucleotide polymorphisms (SNPs) that are robustly associated with chronic lymphocytic leukaemia (CLL) risk. Given that most of these SNPs map to non‐coding regions of the genome, it suggests that the functional basis of many GWAS signals will be through differential gene expression. By referencing publically accessible expression quantitative trait loci (eQTL) data on lymphoblastoid cells lines (LCLs) we have globally demonstrated an association between GWAS P‐values and eQTLs, consistent with much of the variation in CLL risk being defined by variants impacting on gene expression. To explore using eQTL data to select GWAS SNPs for replication, we genotyped rs2072135 (GWAS P‐value = 0·0024, eQTL P‐value = 1·510^?19) in five independent case‐control series totalling 1968 cases and 3538 controls. While not attaining statistical significance (combined P‐value = 1 × 10^?4), rs2072135 defines a promising risk locus for CLL. Incorporating eQTL information offers an attractive strategy for selecting SNPs from GWAS for validation.     

The role of a nonsynonymous CD226 (DNAX-accessory molecule-1) variant (Gly 307Ser) in isolated Addison's disease and autoimmune polyendocrinopathy type 2 pathogenesis

Context Genome‐wide association studies have discovered various susceptibility alleles that are shared among different autoimmune conditions, implicating several biochemical pathways in the pathogenesis of autoimmunity. A nonsynonymous polymorphism in exon 7 of the gene encoding the lymphocyte cell‐surface CD226 (DNAM1) receptor, Gly307Ser (rs763361), has recently been identified as conferring risk to many autoimmune disorders. We performed a case–control study to determine if the CD226 307Ser variant is also associated with autoimmune Addison’s disease (AAD). Patient and design We genotyped rs763361 in a UK cohort of 326 AAD subjects [183 with associated autoimmune conditions – autoimmune polyendocrinopathy syndrome type‐2 (APS2)] and 311 healthy controls, using a Taqman genotyping assay. Results The susceptibility ‘T’ allele at rs763361 was found in 50·5% of patients with AAD compared to 46·5% of controls (P‐value 0·16, OR 1·17; 95% CI 0·94–1·46). However, comparing the APS2 subgroup to healthy controls, the T allele was found in 53·8%vs 46·5% in controls (OR 1·34; CI 1·04–1·74, P‐value 0·03). In contrast, the T allele frequency was 46·2% in isolated Addison’s disease (P‐value 0·94 vs healthy controls). Conclusion It seems likely that the 307Ser variant of the CD226 receptor is associated with APS2 because of its underlying association with type 1 diabetes and autoimmune thyroid disease. The strength of association in patients with isolated AAD appears to be weak or nonexistent compared to that in APS2.     

Association between a variation in LRCH1 and knee osteoarthritis: A genome‐wide single‐nucleotide polymorphism association study using DNA pooling

Objective

To perform a large‐scale association analysis of single‐nucleotide polymorphisms (SNPs) in patients with radiographically defined osteoarthritis (OA) of the knee.

Methods

We examined >25,000 SNPs located within ∼14,000 genes for associations with radiographically defined knee OA, using polymerase chain reaction and MassExtend amplification techniques. Allele frequencies were estimated initially in DNA pools from 335 female patients with knee OA and 335 asymptomatic and radiographically negative female control subjects. All were of northern European ancestry. Significant allele frequency differences were validated by genotyping of individual DNA samples. Confirmed significant findings were verified in 2 additional case–control samples from the UK (443 cases and 303 controls) and Newfoundland (346 cases and 264 controls). Chondrosarcoma cell lines were used to test for potential differences in gene expression.

Results

The marker most strongly associated with the risk of knee OA was rs912428, a C/T polymorphism in intron 1 of LRCH1, a gene on chromosome 13q14 that encodes a novel protein of as‐yet‐unknown function. The frequency of the T allele compared with controls was consistently increased by 40% across all 3 case–control groups. Additional subanalyses in case–control samples with hip OA and hand OA suggested similar trends, but did not reach statistical significance. Association fine‐mapping using 10 additional SNPs in LRCH1 confirmed intron 1 as the region of highest association but failed to reveal variations with significance stronger than the marker SNP, as did the haplotype analysis. LRCH1 was not up‐regulated or overexpressed in chondrosarcoma cell lines exposed to inflammatory stimuli, suggesting a possible structural role.

Conclusion

A genetic variant in LRCH1 was consistently associated with knee OA in 3 samples from 2 populations. Our results also suggest that the same association with OA may exist at other sites. Additional genetic and experimental work is needed to elucidate the precise mechanism by which the LRCH1 gene influences OA risk.

     

Presence of spondyloarthropathy and its clinical profile in patients with hypoparathyroidism

Background Though spondyloarthropathy has been described in patients with sporadic idiopathic hypoparathyroidism (SIH), the clinical profile is not known. Objectives To describe the clinical profile including radiological features of spondyloarthropathy and prevalence of HLA‐B27 allele in patients with hypoparathyroidism, and to identify any differences from ankylosing spondylitis. Subjects and methods Clinical characteristics and radiographs of pelvis and spine were assessed in 40 consecutive patients with SIH. Radiographs were assessed by radiologist (RS) and rheumatologist (RG) for the features of spondyloarthropathy including sacroiliitis, syndesmophytes and hip joint calcification, and so on. HLA‐B27 genotyping was carried out in patients with SIH, and 195 healthy controls using duplex PCR. Fourteen control radiographs were from age‐matched normal individuals. Results Three patients with SIH had clinically overt spondyloarthropathy which closely resembled ankylosing spondylitis. Fourteen (eight females and six males) of the 40 patients with SIH showed radiological changes including syndesmophytes in lower dorsal or dorso‐lumbar spine (n = 6), sacroiliitis and new bone formation at the acetabular rim of the hip joint (n = 10). Though all six patients demonstrating syndesmophytes had new bone formation at hip, sacroiliitis was seen in only three of them. None of the 14 controls had syndesmophytes, sacroiliitis or hip joint calcification. The mean (SD) duration of illness (15·4 ± 8·7 vs. 6·5 ± 5·9 years, P < 0·01), BMI (24·1 ± 5·2 vs. 20·8 ± 3·7 kg/m², P = 0·04) and frequency of basal ganglia calcification was higher (100%vs. 57·7%, P < 0·01) in patients who showed changes of spondyloarthropathy in comparison to those without these changes. On multiple logistic regression analysis, only duration of hypoparathyroid illness was associated with spondyloarthropathy with an odds ratio of 1·17 (95% CI = 1·05–1·30, P < 0·01) per year increase in the duration. The mean age, serum total calcium, inorganic phosphorus and serum intact PTH (iPTH) levels were not significantly different between SIH patients with and without spondyloarthropathy. The frequency of HLA‐B27 allele was comparable between SIH and the control groups. Conclusions Thus, spondyloarthropathy is a distinct clinical entity in patients with SIH. Its salient clinical features include presence of syndesmophytes at the thoracic or thoraco‐lumbar spine, mild sacroiliitis, calcification at the acetabular margin of hip, preserved bone density, equal distribution in both sexes and lack of HLA‐B27 association. Presence of spondyloarthropathy, like basal ganglia calcification, is associated with longer duration of hypoparathyroidism. It is important to differentiate hypoparathyroid‐related spondyloarthropathy from ankylosing spondylitis because the management for the two disorders is different.     

Association of IRF5 polymorphisms with systemic lupus erythematosus in a Japanese population: support for a crucial role of intron 1 polymorphisms

OBJECTIVE: To determine whether the IRF5 gene, which encodes interferon regulatory factor 5, is associated with systemic lupus erythematosus (SLE) in a Japanese population. METHODS: A case-control study was performed in 277 SLE patients and 201 healthy controls. Associations between the IRF5 genotype and levels of messenger RNA (mRNA) for interferon (IFN) pathway genes were examined using an mRNA expression database of HapMap samples. RESULTS: Carriers of the rs2004640T single-nucleotide polymorphism (SNP) were slightly increased among SLE patients (58.8%) as compared with controls (50.2%). When data from our Japanese population were combined with previously published data from a Korean population, the T allele frequency was found to be significantly increased in SLE patients (P = 8.3 x 10(-5)). While no association was observed for the rs10954213 SNP or the exon 6 insertion/deletion, significant associations with 3 intron 1 SNPs (-4001, rs6953165, and rs41298401) were found. The allele frequency of rs41298401G was significantly decreased in SLE patients (13.0% versus 18.7% in controls; P = 0.017), and the allele frequency of rs6953165G, which was in absolute linkage disequilibrium with -4001A, was increased in SLE patients (8.8% versus 5.2% in controls; P = 0.034). The Caucasian risk haplotype was not present; instead, a protective haplotype carrying rs2004640G, rs41298401G, the deletion in exon 6, and rs10954213A was identified. SNP rs10954213, but not intron 1 SNPs, was associated with IRF5 at the mRNA level; nevertheless, intron 1 SNPs were also associated with levels of mRNA for several IFN pathway genes, suggesting a functional role. CONCLUSION: IRF5 was found to be associated with SLE in Asian populations. Intron 1 SNPs, rather than exon 6 and 3'-untranslated region polymorphisms, appeared to play a crucial role.     

Genome‐wide SNP genotyping study using pooled DNA to identify candidate markers mediating susceptibility to end‐stage renal disease attributed to Type 1 diabetes

Aims Genetic factors play a major role in the progression of kidney disease in diabetes. To identify candidate single nucleotide polymorphisms (SNPs) with potential effects on susceptibility to end‐stage renal disease (ESRD), we performed a whole genome association scan using pooled DNA from Caucasian individuals with Type 1 diabetes. Methods We utilized the Illumina Infinium II HumanHap 550 beadchip platform to genotype 555 352 SNPs in DNA pools comprised of 547 cases with ESRD and 549 control subjects with Type 1 diabetes duration > 20 years and no ESRD. Pooled probe intensity was used to predict mean allele frequency (MAF) for each locus. Individual genotyping was performed using the iPLEX assay in conjunction with the MassARRAY platform (Sequenom). Results We identified 2870 markers showing substantial differences in MAF (5.0–10.7%) between pools. To initiate validation of these findings, we genotyped 22 high‐ranking markers in 462 individuals with ESRD and 470 unaffected control subjects selected from the genome‐wide SNP genotyping study sample. We observed the strongest evidence for association between ESRD and rs1749824, located in the ZMIZ1 gene [OR = 1.47 (1.21–1.78) per copy of T allele; P = 8.1 × 10^?5] and rs9298190, located in the musculin gene [OR = 1.56 (1.28–1.91) per copy of C allele; P = 1.6 × 10^?5]. Evidence for nominal association with markers in or near the IRS2, TMPO, BID, KLRA1, ELMO1 and CNDP1 genes was also observed (P ≤ 0.0006). Conclusions These findings identify several novel loci which may contribute to ESRD susceptibility in individuals with Type 1 diabetes.     

Predisposition to vitamin D deficiency osteomalacia and rickets in females is linked to their 25(OH)D and calcium intake rather than vitamin D receptor gene polymorphism

Background Osteomalacia (OSM) and rickets are widely prevalent in developing countries especially in females. The factors associated with such predisposition are not known. Objectives To identify nutritional, endocrine and genetic factors related to calcium and vitamin D metabolism that are associated with OSM/rickets in females. Subjects and methods We studied 98 patients with OSM or rickets and their relatives including male and female sibs and parents (n = 221) for the presence of biochemical OSM {low serum 25‐hydroxyvitamin D [25(OH)D], raised intact PTH (iPTH) and raised alkaline phosphatase} and associated nutritional and genetic factors. Polymerase chain reaction restriction fragment length polymorphism (PCR‐RFLP) was used for genotyping vitamin D receptor (VDR) (BsmI and FokI) and PTH gene (BstBI and DraII) single nucleotide polymorphisms (SNPs) in 74 families. The differences in the factors associated with calcium and vitamin D among the different groups were analysed by analysis of variance (ANOVA). Logistic regression analysis and the transmission disequilibrium test (TDT) were carried out to assess association between nutritional and genetic factors, and the disease, respectively. Results Most of the patients were female (91·8%). The mean serum 25(OH)D level of the female patients was comparable to that of the female sibs (14·4 ± 5·7 vs. 18·3 ± 9·7 nmol/l). The frequency of biochemical OSM was fivefold higher in female than in male sibs (24·4%vs. 4·9%). Female sibs also had significantly lower 25(OH)D, dietary calcium intake and sunshine exposure than male sibs. The frequency of biochemical OSM was comparable between mothers and fathers. The odds of biochemical OSM in the family members was reduced by 11% per 15‐min daily sunshine exposure [odds ratio (OR) = 0·89, 95% confidence interval (CI) = 0·81–0·98, P = 0·02] and decreased by 20% per 100 mg dietary calcium intake (OR = 0·80, 95% CI = 0·67–0·96, P = 0·02). VDR/PTH gene SNPs showed no association with OSM/rickets on TDT analysis. Conclusion Among the immediate family members of patients with OSM/rickets, female sibs have features of biochemical OSM in up to 24·4%. Female sibs, unlike male sibs, share with patients features of markedly low serum 25(OH)D levels, poor dietary calcium intake and poor exposure to sunshine. Genetic factors such as VDR and PTH gene SNPs were not associated with OSM/rickets.     

Association between <Emphasis Type="Italic">SLC2A9</Emphasis> (<Emphasis Type="Italic">GLUT9</Emphasis>) gene polymorphisms and gout susceptibility: an updated meta-analysis

The relationship between the SLC2A9 (solute carrier family 2, member 9) gene polymorphisms and gout was still inconsistent among the individual genetic association studies. Therefore, this present research was aimed to systematically evaluate the association between SLC2A9 gene polymorphisms and gout susceptibility. Relevant studies were enrolled by searching databases systematically. The pooled odds ratios (ORs) with 95 % confidence intervals (CIs) were used to assess the associations. The heterogeneity between each of the studies was calculated by using the Q statistic methods, and Begg’s funnel plot and Egger’s tests were performed to evaluate publication bias. A total of 13 studies investigated four single nucleotide polymorphisms (SNPs) in SLC2A9 were included. In this study, we found that the allele C of rs3733591 was higher in patients than in controls in both all-pooled population [C vs. T: OR (95 % CI) = 1.432 (1.213–1.691)] and Asians-pooled population [C vs. T: OR (95 % CI) = 1.583 (1.365–1.835)]. The allele frequency C of s6449213 was lower in the gout patients than in controls in both all-pooled population and Caucasians-pooled population. Additionally, the allele frequency T of rs16890979 and the allele frequency C of rs1014290 were lower in gout patients than in controls. This study demonstrated that the genetic susceptibility for gout is associated with the SLC2A9 gene polymorphisms. Four of them except for the rs3733591 are protective SNPs in Caucasians, and rs16890979 and rs1014290 are protective SNPs in both Caucasians and Asians, while rs3733591 may be susceptibility SNP in Asians.     

Study of functional variants of the BANK1 gene in rheumatoid arthritis

Objective

To investigate 1 functional (rs17266594) and 2 potentially functional (rs10516487 and rs3733197) BANK1 variants, which were previously identified as systemic lupus erythematosus (SLE) susceptibility markers, to test whether they are associated with rheumatoid arthritis (RA).

Methods

Four different cohorts were included in the study: 1,080 RA patients and 1,368 healthy controls from Spain, 278 RA patients and 568 healthy controls from Sweden, 288 RA patients and 287 healthy controls from Argentina, and 288 RA patients and 288 healthy controls from Mexico. Samples were genotyped for BANK1 single‐nucleotide polymorphisms (SNPs) using a TaqMan 5′‐allele discrimination assay. Statistical analysis comparing allele and genotype distributions was performed with the chi‐square test.

Results

We did not find a significant association between RA and the rs10516487 and rs17266594 BANK1 polymorphisms. However, there was an increase in the major alleles among RA patients. Similarly, for rs3733197, there was an increase in the major allele among patients in every cohort. Nevertheless, this skewing reached statistical significance in the Spanish (P = 0.01, odds ratio [OR] 1.17 [95% confidence interval (95% CI) 1.03–1.32]) and Argentinean (P = 0.04, OR 1.31 [95% CI 1.00–1.72]) populations. We found a significant association of rs10516487 (P = 0.005, OR 1.15 [95% CI 1.04–1.28]) and rs3733197 (P = 0.0009, OR 1.17 [95% CI 1.07–1.29]) with RA in the pooled analysis. In a 3‐SNP haplotype analysis, we found that the major TGG haplotype was significantly associated with RA (P = 0.005, OR 1.14 [95% CI 1.04–1.25]). In addition, we found a common CAA haplotype that was protective against RA (P = 0.0004, OR 0.82 [95% CI 0.74–0.92]).

Conclusion

These results suggest that BANK1 SNPs and haplotypes may contribute to RA susceptibility with a low risk.

     

Association of FcGRIIa with Graves’ disease: a potential role for dysregulated autoantibody clearance in disease onset/progression

Objective Although autoantibody production is a key feature of autoimmunity, it is not known whether variation in autoantibody production and clearance pathways is involved in disease susceptibility. The Fc Gamma Receptor IIa (FcGRIIa) molecule is involved in the clearance of autoantibodies and a functional single nucleotide polymorphism (SNP), rs1801274, which has been shown to alter autoantibody clearance, has been associated with a number of autoimmune diseases (AIDs) including systemic lupus erythematosus and type 1 diabetes. This study aimed to determine whether FcGRIIa is associated with Graves’ disease (GD) in the UK Caucasian population by Tag SNP screening common polymorphisms within the FcGRIIa region. Design A case control association study investigating nine Tag SNPs within FcGRIIa, which captured the majority of known common variation within this gene region. Patients A dataset comprising 2504 UK Caucasian GD patients and 2784 geographically matched controls taken from the 1958 British Birth cohort. Measurements We used the χ²‐test to investigate association between the Tag SNPs and GD. Results Association between the rs1801274 (P = 0·003, OR = 1·12 [95% CI = 1·03–1·22] and rs6427598 (P = 0·012, OR = 0·90 [95% CI = 0·83‐0·98]) SNPs and GD was observed. No other SNPs showed association with GD. No associations were seen between any of the SNPs investigated and specific GD clinical phenotypes. Conclusions This study suggests that variation in FcGRIIa predisposes to GD and further supports the role of FcGRIIa as a susceptibility locus for AIDs in general.     

Insulin-like growth factor-1 deficiency determines increased intima-media thickness at common carotid arteries in adult patients with growth hormone deficiency

objective To investigate the role of IGF‐1 on intima–media thickness (IMT) at common carotid arteries by Doppler ultrasonography. subjects Thirty‐nine patients (17 women, 22 men, aged 25–70 years) with severe GH deficiency (GHD), 19 with normal and 20 with low IGF‐1 levels, and 39 sex‐, age‐ and body mass index (BMI)‐matched healthy controls. results Patients with GHD showed abnormalities in lipid profile, and increased fibrinogen levels, mean IMT (0·88 ± 0·26 vs. 0·69 ± 0·14 mm, P < 0·001), and systolic and diastolic peak velocity (P < 0·001) compared to controls. Eight patients (18%) and one control (2·1%, P = 0·04) had well‐defined plaques. In controls, but not in patients with GHD, mean carotid IMT was correlated with age (r = 0·78, P < 0·001). In both controls (r = ?0·82; P < 0·0001) and patients with GHD (r = ?0·84, P < 0·0001), serum IGF‐1 levels were inversely correlated with mean IMT at common carotid arteries. At the stepwise multiple regression, the variables most significantly related to IMT in GH‐deficient patients were total cholesterol levels (t = 5·2, P < 0·001), followed by disease duration (t = 2·4, P = 0·02), while in controls the variables most significantly related to IMT were IGF‐1 levels (t = ?9·9, P < 0·001), followed by low density lipoprotein (LDL)‐cholesterol levels (t = ?2·3, P = 0·02). Compared to patients with normal IGF‐1 levels, those with low IGF‐1 levels had lower high density lipoprotein (HDL)‐cholesterol levels (1·0 ± 0·2 vs. 1·3 ± 0·2 mmol/l, P = 0·0002), and higher glucose (54·3 ± 6·1 vs. 48·9 ± 5·9 mmol/l, P = 0·008), insulin (25·2 ± 6·8 vs. 18·8 ± 6·0 mUl/l, P = 0·004), total cholesterol (7·1 ± 1·1 vs. 4·9 ± 0·6 mmol/l, P < 0·0001), total/HDL‐cholesterol ratio (7·2 ± 1·8 vs. 3·9 ± 0·7, P < 0·0001), fibrinogen levels (319·8 ± 56·9 vs. 241·8 ± 53·0 mg/dl, P < 0·0001) and mean IMT at common carotid arteries (1·05 ± 0·25 vs. 0·69 ± 0·07 mm, P < 0·0001). Atherosclerotic plaques were found only in GH‐deficient patients with low IGF‐1 levels. conclusions GH‐deficient patients have alterations in lipid profile with an increase in the total/HDL‐cholesterol ratio, which is an index of increased cardiovascular risk, but only patients with IGF‐1 deficiency have increased IMT.     

Polymorphic miRNA‐mediated gene contribution to inhibitor development in haemophilia A

Development of inhibitory antibodies is perhaps the most serious complication of FVIII replacement therapy, precluding efficient clinical management of patients with haemophilia A (HA). The development and function of immune system are also regulated by microRNAs (miRNAs). Mutations and changes in the level of expression of some miRNA genes have been associated with the onset and progression of immunological disorders. The aim of this study was to investigate new genetic polymorphisms in loci for miRNA and their targets to evaluate whether these SNPs may confer susceptibility to inhibitor development in patients with HA. Italian HA patients with and without inhibitors and healthy controls were recruited in this study. For SNP analysis, standard DNA sequencing method was used. We have studied four SNPs, i.e. rs36101366, rs34683807, rs1803603 and rs3024496 located in the 3′UTR of F8 and IL‐10 genes. These SNPs have been checked for their frequencies in patients with and without inhibitors, but no statistically significant differences were found. Then, we have searched for other genetic variants in loci for haematopoietic‐specific miRNAs, i.e. hsa‐mir‐150, hsa‐mir‐155, hsa‐mir‐146a, hsa‐mir‐142, hsa‐mir‐181a and in a specific miRNA, hsa‐mir‐1184, i.e. predicted to be located in the intron 22 of F8 gene. For all miRNAs selected, we did not identify any sequence variation in our study population. This is the first study to demonstrate that there was no association between selected SNPs in miRNAs and their targets and the susceptibility to inhibitor development in people affected by HA.