Interaction analysis between BLK rs13277113 polymorphism and BANK1 rs3733197 polymorphism, MMEL1/TNFRSF14 rs3890745 polymorphism in determining susceptibility to rheumatoid arthritis

Inflammatory bowel disease and rheumatoid arthritis share a common genetic structure

Background

The comorbidity rate of inflammatory bowel disease (IBD) and rheumatoid arthritis (RA) is high; nevertheless, the reasons behind this high rate remain unclear. Their similar genetic makeup probably contributes to this comorbidity.

Methods

Based on data obtained from the genome-wide association study of IBD and RA, we first assessed an overall genetic association by performing the linkage disequilibrium score regression (LDSC) analysis. Further, a local correlation analysis was performed by estimating the heritability in summary statistics. Next, the causality between the two diseases was analyzed by two-sample Mendelian randomization (MR). A genetic overlap was analyzed by the conditional/conjoint false discovery rate (cond/conjFDR) method.LDSC with specific expression of gene analysis was performed to identify related tissues between the two diseases. Finally, GWAS multi-trait analysis (MTAG) was also carried out.

Results

IBD and RA are correlated at the genomic level, both overall and locally. The MR results suggested that IBD induced RA. We identified 20 shared loci between IBD and RA on the basis of a conjFDR of <0.01. Additionally, we identified two tissues, namely spleen and small intestine terminal ileum, which were commonly associated with both IBD and RA.

Conclusion

Herein, we proved the presence of a polygenic overlap between the genetic makeup of IBD and RA and provided new insights into the genetic architecture and mechanisms underlying the high comorbidity between these two diseases.

Assessment of genetic polymorphisms within nuclear factor-κB signaling pathway genes in rheumatoid arthritis: Evidence for replication and genetic interaction

OBJECTIVE

This study was performed to replicate the associations of genetic polymorphisms within nuclear factor-κB (NF-κB) signaling pathway genes with rheumatoid arthritis (RA), and to further examine genetic interactions in a Chinese population.

METHODS

A total of eleven single-nucleotide polymorphisms (SNPs) were genotyped in 594 RA patients and 604 healthy controls.

RESULTS

Genetic association analysis revealed that NFKBIE rs2233434, TNIP1 rs10036748 and BLK rs13277113 were significantly associated with RA, cyclic citrullinated peptide (CCP)-positive RA and rheumatoid factor (RF)-positive RA, and TNFAIP3 rs2230926 was significantly associated with CCP-positive RA. Significant additive interaction was observed between NFKB1 rs28362491 and IKBKE rs12142086 (RERI = 0.76, 95% CI 0.13-1.38; AP = 0.57, 95% CI 0.11-1.03), NFKBIE rs2233434 and BLK rs13277113 (RERI = 1.41, 95% CI 0.88-1.94; AP = 0.85, 95% CI 0.50-1.20), NFKBIL rs2071592 and TNIP1 rs10036748 (RERI = 0.59, 95% CI 0.17-1.02; AP = 0.46, 95% CI 0.05-0.87), UBE2L3 rs5754217 and TNFSF4 rs2205960 (RERI = 0.50, 95% CI 0.16-0.84; AP = 0.57, 95% CI 0.09-1.05). Significant multiplicative interaction was detected between BLK rs13277113 and UBE2L3 rs5754217 (p = 0.02), BLK rs13277113 and TNFSF4 rs2205960 (p = 0.03).

CONCLUSIONS

Our results lent further support to the role of NF-κB signaling pathway in the pathogenesis of RA from a genetic perspective.

BLK and BANK1 variants and interactions are associated with susceptibility for primary Sjögren's syndrome and with some clinical features

BLK and BANK1 in primary Sjögren's syndrome (pSS) have scarcely been evaluated and the results are inconclusive. The aim of our study was to determine whether single nucleotide variants (SNVs) located within BLK or BANK1 are associated with susceptibility, clinical and serological features, and smoking in pSS. BLK rs13277113A/G, BANK1 rs10516487G/A and rs3733197G/A were genotyped in 203 cases and 424 controls using a TaqMan® SNP genotyping assay. The BLK rs13277113A allele showed association with pSS under the allelic (OR 1.35, p = 0.02), and recessive (OR 1.83, p = 0.003) model, while, BANK1 rs3733197G/A showed association under the dominant model (OR 2.90, p = 0.043). Interactions between BANK1 and BLK genotypes also showed association (OR 2.36, p < 0.0001). In addition, BLK rs13277113A/G was associated with protection against arthritis and BANK1 rs10516487G/A with both arthritis and keratoconjunctivitis sicca, meanwhile, BANK1 rs3733197G/A was associated with smoking in patients with pSS. This is the first study to describe an association between BLK and susceptibility to pSS in a Latin-American population. Our data also shows a first evidence of association between interactions of BLK and BANK1 in pSS, and association of BLK and BANK1with arthritis, keratoconjunctivitis sicca and smoking in patients with pSS.

Genetic association analysis of ATG16L1 rs2241880, rs6758317 and ATG16L2 rs11235604 polymorphisms with rheumatoid arthritis in a Chinese population

OBJECTIVE

This study was performed to test whether ATG16L1 rs2241880, rs6758317 and ATG16L2 rs11235604 polymorphisms were associated with RA and further examine the genetic interaction between ATG16L1 and ATG16L2 in RA among a Chinese population.

METHODS

A total of 594 RA patients and 604 healthy controls were included, and the genetic polymorphisms were genotyped based on HI-SNP technology.

RESULTS

Significant associations of ATG16L1 rs2241880 polymorphism with RA (T/T versus C/T + C/C, OR = 1.32, 95% CI 1.04-1.67, P = 0.02), cyclic citrullinated peptide (CCP)-positive RA (genotype comparison, P = 5.38 × 10^-3; T/T versus C/T + C/C, OR = 1.45, 95% CI 1.12-1.87, P = 4.86 × 10^-3) and rheumatoid factor (RF)-positive RA (genotype comparison, P = 0.03; T versus C, OR = 1.23, 95% CI 1.01-1.49, P = 0.04; T/T versus C/T + C/C, OR = 1.44, 95% CI 1.10-1.88, P = 7.62 × 10^-3) were found. Significant genetic interaction between ATG16L1 rs2241880 and ATG16L2 rs11235604 was associated RA (P = 0.03), and significant genetic interaction between ATG16L1 rs6758317 and ATG16L2 rs11235604 was associated with RA (P = 7.57 × 10^-3), CCP-positive RA (P = 0.01) and RF-positive RA (P = 0.01). Consistently, stratification analysis found that significant associations of RA with ATG16L1 rs2241880, rs6758317 polymorphisms were only detected among individuals carrying C/T genotype of the ATG16L2 rs11235604 polymorphism.

CONCLUSIONS

Our results indicated that ATG16L1 rs2241880 polymorphism was associated with RA in Chinese population, and provided evidence for genetic interaction between ATG16L1 and ATG16L2 in determing the development of RA, highlighting the involvement of autophagy in the pathogenesis of RA.

Investigating the association of polymorphisms of ANKRD55 and MMEL1 with susceptibility to multiple sclerosis in Iranian population

OBJECTIVE

Multiple sclerosis (MS) is an autoimmune neurological disability in which immune cells attack the myelin sheaths that protect nerve fibers. The pathogenesis of the disease involves both complex genetic effects as well as multifaceted gene-environment interactions. In the present study, we examined the association of two Single nucleotide polymorphisms (SNPs) in ANKRD55 (rs6859219) and MMEL (rs3748816) with MS in the Iranian population. ANKRD55 is specifically expressed in human peripheral blood mononuclear cells and CD4 + T cells, while MMEL1is involved in the degradation of both neuropeptides and β-amyloid.

METHODS

In this case-control study, 110 patients with MS and 110 matched healthy controls were enrolled. The Participants were genotyped for ANKRD55 and MMEL1 SNPs using PCR-RFLP and Real-Time TaqMan SNP Genotyping respectively. The results were finally analyzed using SPSS software version 22.

RESULTS

Our results did not show significant differences in allelic frequencies of two SNPs among cases and controls (P-Value >0.05). However, for ANKRD55 (rs6859219), CA genotype was shown to have a protective effect (p = 0.035 and OR = 0.55), while CC genotype was a susceptive genotype to MS (p = 0.036 and OR = 1.8). There was no significant difference in genotypic frequencies of SNP rs3748816 in MMEL1.

CONCLUSION

We could successfully replicate the association of ANKRD55 (rs6859219) with susceptibility to MS in the Iranian population. Our result can provide an insight into better understanding the pathogenesis of MS and also improve the genetic counseling for patients affected with multiple sclerosis in Iran.

Src Family Protein Kinase Controls the Fate of B Cells in Autoimmune Diseases

There are more than 80 kinds of autoimmune diseases known at present, including rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), systemic sclerosis (SSc), inflammatory bowel disease (IBD), as well as other disorders. Autoimmune diseases have a characteristic of immune responses directly attacking own tissues, leading to systematic inflammation and subsequent tissue damage. B cells play a vital role in the development of autoimmune diseases and differentiate into plasma cells or memory B cells to secrete high-affinity antibody or provide long-lasting function. Drugs targeting B cells show good therapeutic effects for the treatment of autoimmune diseases, such as rituximab (anti-CD20 antibody). Src family protein kinases (SFKs) are believed to play important roles in a variety of cellular functions such as growth, proliferation, and differentiation of B cell via B cell antigen receptor (BCR). Lck/Yes-related novel protein tyrosine kinase (LYN), BLK (B lymphocyte kinase), and Fyn are three different kinds of SFKs mainly expressed in B cells. LYN has a dual role in the BCR signal. On the one hand, positive signals are beneficial to the development and maturation of B cells. On the other hand, LYN can also inhibit excessively activated B cells. BLK is involved in the proliferation, differentiation, and immune tolerance of B lymphocytes, and further affects the function of B cells, which may lead to autoreactive or regulatory cellular responses, increasing the risk of autoimmune diseases. Fyn may affect the development of autoimmune disorders via the differentiation of B cells in the early stage of B cell development. This article reviews the recent advances of SFKs in B lymphocytes in autoimmune diseases.

Assessment of interleukin 6 gene polymorphisms with rheumatoid arthritis

BACKGROUND

Rheumatoid arthritis (RA) is complex autoimmune system disease and significant impact on the health of population in our world. Numerous studies confirmed that genetic factors play a crucial role in the pathogenesis of RA. In this current study, we aimed to investigate IL-6 polymorphisms and RA risk in Chinese Han population.

METHODS

508 RA patients and 494 age- and gender- matched healthy controls were recruited, all subjects were genotyped with an Agena MassARRAY platform. Subsequently, odds ratios (ORs) and 95% confidence intervals (CIs) were calculated by unconditional logistic regression after adjusting for age and gender.

RESULTS

Our results suggested that IL-6 rs2243289 allele and genotype frequencies were associated with reduced RA risk under all genetic models (all p < 0.05). Stratification analysis revealed that IL-6 rs2243289 polymorphism was significant associated with decreased the risk of RA in the old groups (age > 54) (all p < 0.05). However, IL-6 rs2069837 and rs1800796 polymorphisms were associated with increased risk of RA among the young groups (age ≤ 54) (all p < 0.05). In addition, subgroup analysis by gender suggested that IL-6 rs2069837 and rs1800796 polymorphism were interacted with increased the risk of RA in males (all p < 0.05). Besides, IL-6 rs2243289 was associated with reduced RA risk in females.

CONCLUSIONS

In conclusion, our results demonstrated the correlation between IL and 6 polymorphisms and RA susceptibility and confirmed for the first time that the relationship was restricted to age and gender in Chinese Han population.

Association of BLK and BANK1 Polymorphisms and Interactions With Rheumatoid Arthritis in a Latin-American Population

Introduction

BLK has been identified as a risk factor to rheumatoid arthritis (RA) primarily in Asian or European-derived populations. However, this finding has not been evaluated in other populations such as Latin-Americans, except for Colombians. On the other hand, BANK1 single nucleotide variants (SNVs) have been scarcely studied in RA patients.

Objective

The aim of this study was to determine whether the BLK rs2736340T/C, rs13277113A/G, and BANK1 rs10516487G/A (R61H) and rs3733197G/A (A383T) polymorphisms are risk factors to RA in a sample of patients from Central Mexico.

Materials and Methods

We studied 957 women; 487 controls and 470 patients with RA by means of a TaqMan® SNP genotyping assay with fluorescent probes for the BLK rs13277113A/G, rs2736340T/C and BANK1 10516487G/A (R61H) and rs3733197G/A (A383T) variants.

Result

The BLK rs2736340T/C and rs13277113A/G variants were associated with risk for RA: C vs T; OR 1.39, p = 0.001, and G vs A; OR 1.37, p = 0.004, respectively. In addition, there was also an association between BANK1 R61H and RA: A vs G; OR 1.49, p = 0.003, but no with BANK1 A383T. We also identified an interaction significant between genotypes of BLK rs2736340T/C-BANK1 rs10516487G/A and RA: OR 1.65, p = 0.0001.

Conclusions

Our data suggest that both BLK and BANK1 confer susceptibility to RA in Mexican patients. The individual association of BANK1 rs1054857G/A with RA had not been previously reported in a particular population (except for pooled patients from several countries), therefore, our study presents the first evidence of association between this BANK1 variant and RA.