The intragenic epistatic association of ADD3 with biliary atresia in Southern Han Chinese population

The association of immune-related genes and the potential role of IL10 with biliary atresia

BACKGROUND

Biliary atresia (BA) is a severe immune-related disease that is characterized by biliary obstruction and cholestasis. The etiology of BA is unclear, our aim was to explore the relationship between biliary tract inflammation and immune-related genes.

METHODS

We selected 14 SNPs in 13 immune-related genes and investigated their associations with BA by using a large case‒control cohort with a total of 503 cases and 1473 controls from southern China.

RESULTS

SNP rs1518111 in interleukin10 (IL10) was identified as associated with BA (P = 5.79E-03; OR: 0.80; 95% CI: 0.68-0.94). The epistatic effects of the following pairwise interactions among these SNPs were associated with BA: signal transducer and activator of transcription 4 (STAT4) and chemokine (C-X-C motif) ligand 3 (CXCL3); STAT4 and damage-regulated autophagy modulator1 (DRAM1); CXCL3 and RAD51 paralog B (RAD51B); and interferon gamma (IFNG) and interleukin26 (IL26). Furthermore, we explored the potential role of IL-10 in the pathogenesis of the neonatal mouse model of BA. IL-10 effectively prevented biliary epithelial cell injury and biliary obstruction in murine BA as well as inhibit the activation of BA-related immune cells.

CONCLUSIONS

In conclusion, this study provided strong evidence implicating IL10 as a susceptibility gene for BA in the southern Chinese population.

IMPACT

This study provided strong evidence implicating IL10 as a susceptibility gene for BA in the southern Chinese population. This study could infer that IL-10 may play a protective role in BA mouse model. We found that four SNPs (rs7574865, rs352038, rs4622329, and rs4902562) have genetic interactions.

Genetic Contributions to Biliary Atresia: A Developmental Cholangiopathy

Biliary atresia (BA) is the most prevalent serious liver disease of infancy and childhood, and the principal indication for liver transplantation in pediatrics. BA is best considered as an idiopathic panbiliary cholangiopathy characterized by obstruction of bile flow and consequent cholestasis presenting during fetal and perinatal periods. While several etiologies have been proposed, each has significant drawbacks that have limited understanding of disease progression and the development of effective treatments. Recently, modern genetic analyses have uncovered gene variants contributing to BA, thereby shifting the paradigm for explaining the BA phenotype from an acquired etiology (e.g., virus, toxin) to one that results from genetically altered cholangiocyte development and function. Herein we review recently reported genetic contributions to BA, highlighting the enhanced representation of variants in biological pathways involving ciliary function, cytoskeletal structure, and inflammation. Finally, we blend these findings as a new framework for understanding the resultant BA phenotype as a developmental cholangiopathy.

The correlation between rs2501577 gene polymorphism and biliary atresia: a systematic review and meta-analysis

IMPORTANCE

Multiple studies indicate a possible correlation between ADD3 rs2501577 and biliary atresia susceptibility; however, a conclusive determination has yet to be made.

OBJECTIVE

Investigate the role of ADD3 rs2501577 in biliary atresia susceptibility across diverse populations.

DATA SOURCES

The study protocol has been registered on PROSPERO, an international platform for systematic review registration (PROSPERO ID: CRD42023384641). The following databases will be searched until February 1, 2023: PubMed, Embase, Cochrane, CBM, Web of Science, and CNKI.

STUDY SELECTION

Eight studies were selected from seven papers to assess the data. A total of 7651 participants were included, consisting of 1662 in the BA group and 5989 in the NC group.

DATA EXTRACTION AND SYNTHESIS

Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed while conducting the systematic reviews and meta-analyses. Two authors independently assessed the quality of the included studies using the Newcastle-Ottawa Quality Assessment Scale. The significance of the pooled odds ratio (OR) was evaluated with a Z test, and statistical heterogeneity across studies was assessed using the I2 and Q statistics. Publication bias was assessed using Egger's and Begg's tests.

MAIN OUTCOME(S) AND MEASURE(S)

The primary study outcome was the development of biliary atresia. Subgroup analysis was performed based on race, region, and assessment of Hardy-Weinberg equilibrium (HWE).

RESULTS

The studies indicate that the ADD3 rs2501577 susceptibility locus increases the risk of developing biliary atresia, regardless of allelic, homozygote, dominant, and recessive gene inheritance models. Furthermore, ADD3 has been found to be associated with apoptosis, cell cycle, and cell damage repair based on functional analysis.

CONCLUSIONS AND RELEVANCE

The ADD3 rs2501577 polymorphic locus is associated with an increased risk of biliary atresia, particularly in Asian populations. This study recommends further investigation of the ADD3 rs2501577 locus in Asian populations to validate its role in the diagnosis of biliary atresia.

MiR-100 rs1834306 A>G Increases Biliary Atresia Risk in Southern Han Chinese Children

Background

Biliary atresia (BA) is a type of severe cholestatic childhood disease that may have a genetic component. miR-100 plays a key role in regulating cell apoptosis, proliferation, and inflammatory reactions. A single-nucleotide polymorphism in miR-100 has been proven to modulate susceptibility to various diseases.

Methods

We conducted a case-control retrospective study to explore the correlation between miR-100 gene polymorphism (rs1834306 A>G) and biliary atresia susceptibility in 484 Chinese patients and 1445 matched control subjects.

Results

Our results showed that rs1834306 A>G was correlated with a significantly increased risk for BA (GG vs. AA: adjusted odds ratio (OR) = 1.44, 95%confidence interval (CI) = 1.02-2.03, p = 0.041; and GG vs. AA/AG: adjusted OR = 1.39, 95%CI = 1.02-1.89, p = 0.036).

Conclusions

Our results showed that the rs1834306 A>G polymorphism is associated with an increased risk for BA and contributes to BA susceptibility.

Biliary Atresia: A Complex Hepatobiliary Disease with Variable Gene Involvement, Diagnostic Procedures, and Prognosis

The diagnosis of biliary atresia is still terrifying at the 3rd decade of the 21st century. In a department of neonatal intensive care unit, parents and physicians face a challenge with a jaundiced baby, who may or may not have a surgically correctable hepatopathy. The approach has been systematically evaluated, but the etiology remains ambiguous. The study of families with recurrent biliary atresia has been undertaken at a molecular level. The primary interest with this disease is to identify the etiology and change the treatment from symptomatic to curative. The occurrence of this obstructive cholangio-hepatopathy in well-known genetic syndromes has suggested just coincidental finding, but the reality can be more intriguing because some of these diseases may have some interaction with the development of the intrahepatic biliary system. Several genes have been investigated thoroughly, including ADD3 and GPC1 shifting the interest from viruses to genetics. In this review, the intriguing complexities of this hepatobiliary disease are highlighted.

Genetic aspects of biliary atresia etiology

Biliary atresia (BA) is a cholestatic disorder of infancy that is fatal if untreated. Despite years of study the etiology of BA remains unknown. Three etiopathogenic mechanisms may be involved, such as immune dysregulation, environmental factors and genetic susceptibility. Genetic predisposition is being actively studied. Candidate genes associated with BA in certain populations, genes affecting the cholangiocyte cilia function, as well as genes involved in stress responses have been identified. However, the long-term follow-up of twins with BA suggests that genotype is not of paramount importance for the disease development. Both epigenetic patterns and postzygotic somatic mutations may contribute to etiology of the disease. Recently, some evidence is being accumulated on the possible genetic predisposition to certain outcome of Kasai portoenterostomy performed in patients with BA. However, the presence of a number of factors contributing to the development of the disease makes it difficult to identify the genetic markers.

Association of common variation in ADD3 and GPC1 with biliary atresia susceptibility

Biliary atresia (BA) is an idiopathic neonatal cholestatic disease. Recent genome-wide association study (GWAS) revealed that common variation of ADD3, GPC1, ARF6, and EFEMP1 gene was associated with BA susceptibility. We aimed to evaluate the association of these genes with BA in Chinese population. Twenty single nucleotide polymorphisms (SNPs) in these four genes were genotyped in 340 BA patients and 1,665 controls. Three SNPs in ADD3 were significantly associated with BA, and rs17095355 was the top SNP (P_Allele = 3.23×10^-6). Meta-analysis of published data and current data indicated that rs17095355 was associated with BA susceptibility in Asians and Caucasians. Three associated SNPs were expression quantitative trait loci (eQTL) for ADD3. Two GPC1 SNPs in high linkage disequilibrium (LD) showed nominal association with BA susceptibility (P_Allele = 0.03 for rs6707262 and P_Allele = 0.04 for rs6750380), and were eQTL of GPC1. Haplotype harboring these two SNPs almost reached the study-wide significance (P = 0.0035). No association for ARF6 and EFEMP1 was found with BA risk in the current population. Our study validated associations of ADD3 and GPC1 SNPs with BA risk in Chinese population and provided evidence of epistatic contributions of genetic factors to BA susceptibility.

Irrelevance of USF2 rs916145 polymorphism with the risk of biliary atresia susceptibility in Southern Chinese children

Backgrounds: Biliary atresia (BA) is a very rare neonatal disease, however, it has been the most common cause of obstructive jaundice in infancy. The complex pathogenesis of BA is not entirely clear and a lot of possible pathogenic mechanisms have been proposed to explain the etiology of BA, including genetic, inflammatory, environmental and developmental abnormalities. As a transcription factor, USF2 gene rs916145 polymorphism has been shown to be related to the risk of BA.

Methods: We examined the USF2 rs916145 genotype in a large case–control study consisting of 506 BA patients and 1473 healthy controls, using the MassARRAY iPLEX Gold system (Sequenom). Odds ratios (ORs) and 95% confidence intervals (CIs) were used to evaluate the association between the USF2 gene rs916145 polymorphism and BA susceptibility.

Results: The frequency of different genotypes showed no statistical significance (GG/GC, OR: 1.09, P=0.470, 95% CI: 0.87–1.35; GG/CC, OR: 0.86, P=0.378, 95% CI: 0.62–1.20). No obvious association was revealed between the USF2 gene rs916145 polymorphism and BA susceptibility.

Conclusion:USF2 rs916145 polymorphism may not be the best predictor of BA.