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Association of Cx43 rs2071166 polymorphism with an increased risk for atrial septal defect

Published online by Cambridge University Press:  04 December 2017

Ruoyi Gu ,
Wei Sheng ,
Xiaojing Ma  and
Guoying Huang
Ruoyi Gu
Affiliation:
Children’s Hospital of Fudan University, Shanghai, China
Wei Sheng
Affiliation:
Children’s Hospital of Fudan University, Shanghai, China
Xiaojing Ma
Affiliation:
Children’s Hospital of Fudan University, Shanghai, China Shanghai Key Laboratory of Birth Defects, Shanghai, China
Guoying Huang*
Affiliation:
Children’s Hospital of Fudan University, Shanghai, China Shanghai Key Laboratory of Birth Defects, Shanghai, China
*
Correspondence to: G. Huang, MD, Pediatric Heart Center, Children’s Hospital of Fudan University, 399 Wanyuan Road, Shanghai 201102, China. Tel: +86-21-64931928; Fax: +86-21-64931928; E-mail: gyhuang@shmu.edu.cn
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Abstract

Atrial septal defect is one of the most common CHD. The pathogenesis of atrial septal defect still remains unknown. Cx43 is the most prevalent connexin in the mammalian heart during development. Its genetic variants can cause several CHD. The aim of our study was to investigate the association of genetic variations of the Cx43 with sporadic atrial septal defect. A total of 450 paediatric patients were recruited, including 150 cases with atrial septal defect and 300 healthy controls. The promoter region of Cx43 was analysed by sequencing after polymerase chain reaction. All data were analysed by using the Statistic Package for Social Science 19.0 software. The frequency of the single nucleotide polymorphism rs2071166 was significantly higher in atrial septal defect cases than in healthy controls. The CC genotype at rs2071166 site in Cx43 was correlated with an increased risk for atrial septal defect (p<0.0001, odds ratio=3.891, 95% confidence interval 1.948–7.772) and the C allele was positively correlated with atrial septal defect (p=0.007, odds ratio=1.567, 95% confidence interval 1.129–2.175). In conclusion, our results confirmed that rs2071166 in Cx43 may be relevant with an increased atrial septal defect risk.

Keywords

Cx43single nucleotide polymorphismatrial septal defect

Information

Type
Original Articles
Information
Cardiology in the Young , Volume 28 , Issue 3 , March 2018 , pp. 397 - 402
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Copyright
© Cambridge University Press 2017 

Atrial septal defect (ASD) is one of the most common CHD. It occurs not only in isolation but also in the presence of other heart defects.Reference Greenway, McLeod and Hume 1 The aetiology of atrial septal defects remains unknown. Some researches in patients with sporadic atrial septal defects have identified pathogenic mutations in several susceptibility genes, for example, GATA4, Nkx2.5, GATA6, and TLL1.Reference Garg, Kathiriya and Barnes 2 – Reference Schott, Benson and Basson 5

Cx43 is one of the most prevalent connexin proteins in the mammalian heart.Reference Salameh, Blanke and Daehnert 6 It has been proved to be important for normal murine heart development.Reference Ewart, Cohen and Meyer 7 – Reference Huang, Wessels, Smith, Linask, Ewart and Lo 9 Researchers established a Cx43 knockout mice, and the fetal mice died at birth because of severe heart malformations.Reference Ewart, Cohen and Meyer 7 , Reference Huang, Wessels, Smith, Linask, Ewart and Lo 9 A functional gap junction channel containing six connexin subunits, the subunits, can form a hemi-channel in the plasma membrane of a cell.Reference Salameh, Blanke and Daehnert 6 Two hemi-channels from nearby cells dock to form an entire channel, which allows for the passage of molecules and ions between the cytoplasm of the two cells.Reference Paznekas, Boyadjiev and Shapiro 10 Gap junctions also have a vital role in the synchronised contraction of the heart and in embryonic development.Reference Schulz, Gorge, Gorbe, Ferdinandy, Lampe and Leybaert 11 Cx43 is mainly expressed in atrial and ventricular myocytes and less expressed in the conduction system such as Purkinje fibres.Reference Severs, Bruce, Dupont and Rothery 12

Although studies showed that Cx43 missense mutations in the coding region was associated with severe heart malformations such as visceroatrial heterotaxia, hypoplastic left heart syndrome, atrioventricular septal defect,Reference Dasgupta, Martinez, Zuppan, Shah, Bailey and Fletcher 13 , Reference Britz-Cunningham, Shah, Zuppan and Fletcher 14 the relationship between genetic variant in non-coding region of Cx43 and atrial septal defect was unclear.

In order to solve this question, we explored whether genetic variants in Cx43 promoter region correlated patients with atrial septal defects.

Materials and methods

Patient characteristics collection

Patients with atrial septal defects were recruited from the Children’s Hospital of Fudan University, Shanghai, China from June, 2013 to March, 2016. Human samples were collected from consenting individuals. The research programme was approved by the Shanghai Medical College of Fudan University. Protocols used in this work were reviewed and approved by the Ethics Committee of Children’s Hospital of Fudan University, Shanghai Medical College of Fudan University before the commencement of the study. All parents or guardians of the recruited children signed a written consent.

Deoxyribonucleic acid sequencing

Genomic deoxyribonucleic acid from 150 patients with atrial septal defects (with median age 24.0 months) and 300 healthy controls (with median age 24.0 months) was extracted from peripheral blood leucocytes using the QIAamp DNA Blood Mini Kit (QIAGEN, Germantown, Maryland, United States of America). The base information of the patients is listed in Table 1. The promoter region ranging from −1000 bp to transcriptional start site of Cx43 was amplified with primers in all patients and controls (Table 2). The programme of polymerase chain reaction cycles have been described previously.Reference Wu, Ma and Wang 15 The polymerase chain reaction products were sequenced by Shanghai Invitrogen Co. Ltd (Shanghai, China). The sequence results were analysed using Mutation Surveyor demo software (SoftGenetics, Nittany Valley, Pennsylvania, United States of America). All variants found by sequencing were filtered from the National Center for Biotechnology Information human single nucleotide polymorphism database and the 1000 Genome Project database. 16

Table 1

Basic characteristic of the atrial septal defect (ASD) patients and controls.

Table 2

Primer pairs of the Cx43 for sequence

Statistical analysis

Data were analysed using Statistic Package for Social Science (version 19.0; IBM, Armonk, New York, United States of America) and GraphPad Prism (version 5.0; GraphPad Software, La Jolla, California, United States of America). Genotype and allele frequencies were assessed by the χ2 test. Hardy–Weinberg equilibrium was assessed by the χ2 test on the website for Hardy–Weinberg disequilibrium test (http://ihg.gsf.de/cgi-bin/hw/hwa1.pl). All statistical analyses were two-sided, and p<0.05 was considered statistically significant.

Results

In the present study, 150 patients with atrial septal defects and 300 healthy controls were recruited. In the control group, distribution of genotype for rs2071166 was in line with Hardy–Weinberg equilibrium (p=0.204). A total of 1000 base pairs of Cx43 promoter region from transcriptional start site were sequenced after polymerase chain reaction. In this region, no mutation was detected in any of the participants. According to our research data, single nucleotide polymorphism rs2071166 located at −416 base pair from the transcriptional start site of Cx43 with minor allele frequency>0.05 in Chinese Han Beijing population. The association of both single nucleotide polymorphism genotypes and allelotypes with the risk for atrial septal defect was analysed. And the single nucleotide polymorphism rs2071166 located within a functional retinoic acid response element (Fig 1, repeating element with black background). 17 , Reference Gu, Xu and Lin 18

Figure 1

Retinoic acid response element sequence of Cx43. The alignments showed the retinoic acid response element sequence of Cx43 was conserved among primates (repeating element with black background). The SNP site was marked by bold-type letter.

We identified two alleles (A and C) and three genotypes (AA, AC, and CC) at rs2071166 in both groups (Fig 2, Table 3). The frequency of Cx43 rs2071166 genotypes were 62.7% (AA), 21.3% (AC), 16% (CC) in patients with atrial septal defects and 67.0% (AA), 28.3% (AC), 4.7% (CC) in healthy controls (Table 3). The frequency distribution of three genotypes had significant difference between atrial septal defect cases and healthy controls (p=0.0002, Table 3). The logistic regression analysis revealed that CC genotype was correlated with atrial septal defect (p<0.0001, odds ratio=3.891, 95% CI 1.948–7.772, Table 4). As shown in Table 5, the minor allele C of rs207116 showed a significantly higher frequency in the patients with atrial septal defects than in the control group (p=0.007), and the logistic regression analysis revealed that C allele was correlated with atrial septal defect (p=0.007, odds ratio=1.567, 95% CI 1.129–2.175).

Figure 2

Sequence diagram of rs2071166 site with different genotype. Arrows indicated the single nucleotide polymorphism site. Genotype: ( a ) AA; ( b ) AC; ( c ) CC. Green, black, red, and blue, respectively, represented A allele, G allele, T allele, and C allele.

Table 3

Association between genotypes of rs2071166.

ASD=atrial septal defect

Table 4

Association between genotypes of rs2071166 and the risk of atrial septal defect (ASD).

Table 5

Association between allelotypes of rs2071166 and the risk of atrial septal defect (ASD).

Discussion

The reported Cx43 mutations include missense, nonsense, insertion, and deletion mutations.Reference Paznekas, Boyadjiev and Shapiro 10 , Reference Huang, Xie and Linask 19 , Reference Paznekas, Karczeski and Vermeer 20 Mutations in the coding region can affect the protein function or inhibit its expression; most of the relative researches focus on this genetic region. Mutations in Cx43 coding region have been proved in patients with oculodentodigital dysplasia.Reference Paznekas, Boyadjiev and Shapiro 10 In that study, cardiac abnormalities were rare; only one patient with Gly21Arg mutation was associated with atrioseptal defects.Reference Paznekas, Boyadjiev and Shapiro 10 Our previous study found no amino acid altering mutation or deoxyribonucleic acid variants in Cx43 gene in 300 patients with CHD.Reference Huang, Xie and Linask 19 We also generated knock-in mouse models with point mutations at serine residues in our previous study; however, both heterozygous and homozygous knock-in mice did not show overt CHD.Reference Huang, Xie and Linask 19 Although patients with hypoplastic left heart syndrome, visceroatrial heterotaxia, or double outlet right ventricle were found to exhibit point mutations in Cx43 at protein residues,Reference Dasgupta, Martinez, Zuppan, Shah, Bailey and Fletcher 13 , Reference Britz-Cunningham, Shah, Zuppan and Fletcher 14 , Reference Chen, Xie, Huang, Zhao and Chang 21 the clinical findings were not replicated in subsequent studies.Reference De Luca, Sarkozy and Consoli 22 – Reference Debrus, Tuffery and Matsuoka 24 Therefore, the contribution of Cx43 mutations at the coding region in human CHD remains open to debate.

Recently, investigators thought that the non-coding regions containing 5′-untranslated regions (UTR), 3′-untranslated regions, promoter region, and enhancer region also play an important role in the occurrence of CHD.Reference Cao, Wang and Wei 25 The mutations or genetic variants in these regions can reduce the protein physiological levels of the gene by lowering the protein transcription efficiency, impacting ribonucleic acid splicing, disrupting the combination of transcription factors with cofactors, or changing the methylation status of deoxyribonucleic acid.Reference Huang 26

In recent studies, single nucleotide polymorphisms were identified to influence the development of CHD, such as polymorphisms in gene MTHFR, eNOS, VEGF, SERPINE1, and other related genes.Reference Muntean, Toganel and Benedek 27 – Reference Loukanov, Hoss and Tonchev 31 They were associated with pulmonary valve stenosis, hypoplastic left heart syndrome, coarctation of the aorta, aortic valve stenosis, tetralogy of Fallot, and ventricular septal defect.Reference Rossaak, Van Rij, Jones and Harris 30 , Reference Lambrechts, Devriendt and Driscoll 32 – Reference Wang, Hou, Wang, Wei, Li and Jiang 34 As a result, researchers thought that single nucleotide polymorphisms might have an effect on cardiac phenotype, but they could not explain consistently the phenotypic diversity in different disease.Reference Muntean, Toganel and Benedek 27

This is the first time we detected a genetic variant in the non-coding region of Cx43 among human patients with sporadic atrial septal defect. We identified the rs2071166 was significantly associated with the risk for atrial septal defects. According to our results, C allele of this single nucleotide polymorphism was a risk factor for causing atrial septal defect. We exploring the genotype further, data showed patients with the CC genotype of atrial septal defect were at a higher frequency than those with AA/AC genotype.

Genome-wide association studies demonstrated that a large number of non-coding variants might contribute to an increase in the risk for various common diseases, often by disrupting cis-regulatory elements that control the expression of nearby genes.Reference Harismendy, Notani and Song 35 – Reference Lubbe, Pittman and Olver 37 Cx43 was dosage-sensitive during embryonic development. Less or too much expression of Cx43 would lead to heart development abnormalities.Reference Ewart, Cohen and Meyer 7 – Reference Huang, Wessels, Smith, Linask, Ewart and Lo 9 , Reference Kolcz, Drukala, Bzowska, Rajwa, Korohoda and Malec 38 The rs2071166 is located within a functional retinoic acid response element.Reference Gu, Xu and Lin 18 The retinoic acid response element was critical in retinoic acid regulating Cx43 transcription activity and expression level.Reference Gu, Xu and Lin 18 Thus, we speculated that this single nucleotide polymorphism might change the efficiency of Cx43 transcription through damaging the function of the retinoic acid response element in Cx43. To further investigate our hypothesis, more molecular biology experiments such as luciferase transfection assay, electrophoretic mobility shift assay (EMSA), and transgenic knock-in animal models should be carried out to figure out the mechanism in CC genotype at rs2071166 affecting the retinoic acid response element in Cx43 and analyse the phenotype of the embryo heart.

In conclusion, Cx43 genetic polymorphisms rs2071166 may be relevant with an increased atrial septal defect risk.

Acknowledgements

The authors are grateful to all patients for their contribution to the work.

Authors’ Contribution

Conception and study design: G.H., X.M., and R.G. Data analysis: R.G. Drafting: R.G. and W.S. Final approval: R.G., W.S., X.M., and G.H.

Financial Support

This work was granted by the Natural Science Foundation of China (81670279, 81370198) and the National Key Research and Development Program of China (2016YFC1000500).

Conflicts of Interest

The authors declare that they have no competing conflicts and interests.

Ethical Standards

The research program was permitted by the Shanghai Medical College of Fudan University. Protocols used in this work were reviewed and approved by the Ethics Committee of Children’s Hospital of Fudan University, Shanghai Medical College of Fudan University prior to the commencement of the study. Patient informed consent from the parents or guardians of the children was obtained.

References

1. Greenway, SC, McLeod, R, Hume, S, et al. Exome sequencing identifies a novel variant in ACTC1 associated with familial atrial septal defect. Can J Cardiol 2014; 30: 181–187.CrossRefGoogle ScholarPubMed
2. Garg, V, Kathiriya, IS, Barnes, R, et al. GATA4 mutations cause human congenital heart defects and reveal an interaction with TBX5. Nature 2003; 424: 443–447.CrossRefGoogle ScholarPubMed
3. Stanczak, P, Witecka, J, Szydlo, A, et al. Mutations in mammalian tolloid-like 1 gene detected in adult patients with ASD. Eur J Hum Genet 2009; 17: 344–351.CrossRefGoogle ScholarPubMed
4. Lin, X, Huo, Z, Liu, X, et al. A novel GATA6 mutation in patients with tetralogy of Fallot or atrial septal defect. J Hum Genet 2010; 55: 662–667.CrossRefGoogle ScholarPubMed
5. Schott, JJ, Benson, DW, Basson, CT, et al. Congenital heart disease caused by mutations in the transcription factor NKX2-5. Science 1998; 281: 108–111.CrossRefGoogle ScholarPubMed
6. Salameh, A, Blanke, K, Daehnert, I. Role of connexins in human congenital heart disease: the chicken and egg problem. Front Pharmacol 2013; 4: 70.CrossRefGoogle ScholarPubMed
7. Ewart, JL, Cohen, MF, Meyer, RA, et al. Heart and neural tube defects in transgenic mice overexpressing the Cx43 gap junction gene. Development 1997; 124: 1281–1292.CrossRefGoogle ScholarPubMed
8. Huang, GY, Cooper, ES, Waldo, K, Kirby, ML, Gilula, NB, Lo, CW. Gap junction-mediated cell-cell communication modulates mouse neural crest migration. J Cell Biol 1998; 143: 1725–1734.CrossRefGoogle ScholarPubMed
9. Huang, GY, Wessels, A, Smith, BR, Linask, KK, Ewart, JL, Lo, CW. Alteration in connexin 43 gap junction gene dosage impairs conotruncal heart development. Dev Biol 1998; 198: 32–44.CrossRefGoogle ScholarPubMed
10. Paznekas, WA, Boyadjiev, SA, Shapiro, RE, et al. Connexin 43 (GJA1) mutations cause the pleiotropic phenotype of oculodentodigital dysplasia. Am J Hum Genet 2003; 72: 408–418.CrossRefGoogle ScholarPubMed
11. Schulz, R, Gorge, PM, Gorbe, A, Ferdinandy, P, Lampe, PD, Leybaert, L. Connexin 43 is an emerging therapeutic target in ischemia/reperfusion injury, cardioprotection and neuroprotection. Pharmacol Ther 2015; 153: 90–106.CrossRefGoogle ScholarPubMed
12. Severs, NJ, Bruce, AF, Dupont, E, Rothery, S. Remodelling of gap junctions and connexin expression in diseased myocardium. Cardiovasc Res 2008; 80: 9–19.CrossRefGoogle ScholarPubMed
13. Dasgupta, C, Martinez, AM, Zuppan, CW, Shah, MM, Bailey, LL, Fletcher, WH. Identification of connexin43 (alpha1) gap junction gene mutations in patients with hypoplastic left heart syndrome by denaturing gradient gel electrophoresis (DGGE). Mutation Res 2001; 479: 173–186.CrossRefGoogle ScholarPubMed
14. Britz-Cunningham, SH, Shah, MM, Zuppan, CW, Fletcher, WH. Mutations of the Connexin43 gap-junction gene in patients with heart malformations and defects of laterality. New Engl J Med 1995; 332: 1323–1329.CrossRefGoogle ScholarPubMed
15. Wu, Y, Ma, XJ, Wang, HJ, et al. Expression of Cx43-related microRNAs in patients with tetralogy of Fallot. World J Pediatr 2014; 10: 138–144.CrossRefGoogle ScholarPubMed
16. http:// browser.1000genomes.org/.Google Scholar
17. http://www.ensembl.org/.Google Scholar
18. Gu, R, Xu, J, Lin, Y, et al. Liganded retinoic acid X receptor alpha represses connexin 43 through a potential retinoic acid response element in the promoter region. Pediatric Res 2016; 80: 159–168.CrossRefGoogle ScholarPubMed
19. Huang, GY, Xie, LJ, Linask, KL, et al. Evaluating the role of connexin43 in congenital heart disease: screening for mutations in patients with outflow tract anomalies and the analysis of knock-in mouse models. J Cardiovasc Dis Res 2011; 2: 206–212.CrossRefGoogle ScholarPubMed
20. Paznekas, WA, Karczeski, B, Vermeer, S, et al. GJA1 mutations, variants, and connexin 43 dysfunction as it relates to the oculodentodigital dysplasia phenotype. Hum Mutat 2009; 30: 724–733.CrossRefGoogle Scholar
21. Chen, P, Xie, LJ, Huang, GY, Zhao, XQ, Chang, C. Mutations of connexin43 in fetuses with congenital heart malformations. Chin Med J 2005; 118: 971–976.Google ScholarPubMed
22. De Luca, A, Sarkozy, A, Consoli, F, et al. Exclusion of Cx43 gene mutation as a major cause of criss-cross heart anomaly in man. Int J Cardiol 2010; 144: 300–302.CrossRefGoogle Scholar
23. Penman Splitt, M, Tsai, MY, Burn, J, Goodship, JA. Absence of mutations in the regulatory domain of the gap junction protein connexin 43 in patients with visceroatrial heterotaxy. Heart 1997; 77: 369–370.CrossRefGoogle Scholar
24. Debrus, S, Tuffery, S, Matsuoka, R, et al. Lack of evidence for connexin 43 gene mutations in human autosomal recessive lateralization defects. J Mol Cell Cardiol 1997; 29: 1423–1431.CrossRefGoogle ScholarPubMed
25. Cao, Y, Wang, J, Wei, C, et al. Genetic variations of NKX2-5 in sporadic atrial septal defect and ventricular septal defect in Chinese Yunnan population. Gene 2015.CrossRefGoogle Scholar
26. Huang, Q. Genetic study of complex diseases in the post-GWAS era. J Genet Genomics 2015; 42: 87–98.CrossRefGoogle ScholarPubMed
27. Muntean, I, Toganel, R, Benedek, T. Genetics of congenital heart disease: past and present. Biochemical Genet 2017; 55: 105–123.CrossRefGoogle ScholarPubMed
28. Junker, R, Kotthoff, S, Vielhaber, H, et al. Infant methylenetetrahydrofolate reductase 677TT genotype is a risk factor for congenital heart disease. Cardiovasc Res 2001; 51: 251–254.CrossRefGoogle ScholarPubMed
29. Xie, J, Yi, L, Xu, ZF, et al. VEGF C-634G polymorphism is associated with protection from isolated ventricular septal defect: case-control and TDT studies. Eur J Hum Genet 2007; 15: 1246–1251.CrossRefGoogle ScholarPubMed
30. Rossaak, JI, Van Rij, AM, Jones, GT, Harris, EL. Association of the 4G/5G polymorphism in the promoter region of plasminogen activator inhibitor-1 with abdominal aortic aneurysms. J Vascular Surgery 2000; 31: 1026–1032.CrossRefGoogle ScholarPubMed
31. Loukanov, T, Hoss, K, Tonchev, P, et al. Endothelial nitric oxide synthase gene polymorphism (Glu298Asp) and acute pulmonary hypertension post cardiopulmonary bypass in children with congenital cardiac diseases. Cardiol Young 2011; 21: 161–169.CrossRefGoogle ScholarPubMed
32. Lambrechts, D, Devriendt, K, Driscoll, DA, et al. Low expression VEGF haplotype increases the risk for tetralogy of Fallot: a family based association study. J Med Genet 2005; 42: 519–522.CrossRefGoogle ScholarPubMed
33. Li, X, Liu, CL, Li, XX, Li, QC, Ma, LM, Liu, GL. VEGF gene polymorphisms are associated with risk of tetralogy of Fallot. Med Sci Monit 2015; 21: 3474–3482.CrossRefGoogle ScholarPubMed
34. Wang, W, Hou, Z, Wang, C, Wei, C, Li, Y, Jiang, L. Association between 5, 10-methylenetetrahydrofolate reductase (MTHFR) polymorphisms and congenital heart disease: a meta-analysis. Meta Gene 2013; 1: 109–125.CrossRefGoogle Scholar
35. Harismendy, O, Notani, D, Song, X, et al. 9p21 DNA variants associated with coronary artery disease impair interferon-gamma signalling response. Nature 2011; 470: 264–268.CrossRefGoogle ScholarPubMed
36. Musunuru, K, Strong, A, Frank-Kamenetsky, M, et al. From noncoding variant to phenotype via SORT1 at the 1p13 cholesterol locus. Nature 2010; 466: 714–719.CrossRefGoogle ScholarPubMed
37. Lubbe, SJ, Pittman, AM, Olver, B, et al. The 14q22.2 colorectal cancer variant rs4444235 shows cis-acting regulation of BMP4. Oncogene 2012; 31: 3777–3784.CrossRefGoogle ScholarPubMed
38. Kolcz, J, Drukala, J, Bzowska, M, Rajwa, B, Korohoda, W, Malec, E. The expression of connexin 43 in children with tetralogy of Fallot. Cell Mol Biol Lett 2005; 10: 287–303.Google ScholarPubMed
Figure 0

Table 1 Basic characteristic of the atrial septal defect (ASD) patients and controls.

Figure 1

Table 2 Primer pairs of the Cx43 for sequence

Figure 2

Figure 1 Retinoic acid response element sequence of Cx43. The alignments showed the retinoic acid response element sequence of Cx43 was conserved among primates (repeating element with black background). The SNP site was marked by bold-type letter.

Figure 3

Figure 2 Sequence diagram of rs2071166 site with different genotype. Arrows indicated the single nucleotide polymorphism site. Genotype: (a) AA; (b) AC; (c) CC. Green, black, red, and blue, respectively, represented A allele, G allele, T allele, and C allele.

Figure 4

Table 3 Association between genotypes of rs2071166.

Figure 5

Table 4 Association between genotypes of rs2071166 and the risk of atrial septal defect (ASD).

Figure 6

Table 5 Association between allelotypes of rs2071166 and the risk of atrial septal defect (ASD).