NKX2-5 molecular screening and assessment of variant rate and risk factors of secundum atrial septal defect in a Moroccan population

A Novel Missense Heterozygous Mutation in NKX2-5 Gene in a Family with Congenital Septal Defects and Cardiomyopathy: Case Series and Literature Review

Single-gene mutations are important causes of congenital heart defects in children. Mutations in the NKX2-5 gene have been recently described in the literature as a cause of septal defects and cardiomyopathy. However, the spectrum of cardiac disease associated with NKX2-5 gene mutations is variable, ranging from asymptomatic septal defects to cardiomyopathy and sudden death. In this case report, we describe a case of 2-year-old child, along with two other family members, with a novel missense heterozygous (c.544G > T p.[Val182Phe]) mutation in NKX2-5 gene consistent with the diagnosis of autosomal dominant atrial septal defects with cardiomyopathy. This report can contribute to the understanding of genotype-phenotype correlations; it emphasizes the significant clinical relevance of NKX2-5 gene defects for congenital heart defects, sudden death, and cardiomyopathy, especially in multiple affected family members. It also suggests that individuals with NKX2-5 mutations are at risk of lethal arrhythmias and conduction disorders, that is why they should be evaluated routinely to assess the need for implantable cardioverter-defibrillator or pacemaker implantation.

NKX2-5 variants screening in patients with atrial septal defect in Indonesia

Background

NKX2-5 variant in atrial septal defect patients has been reported. However, it is not yet been described in the Southeast Asian population. Here, we screened the NKX2-5 variants in patients with atrial septal defect (ASD) in the Indonesian population.

Method

We recruited 97 patients with ASD for genetic screening of the NKX2-5 variant using Sanger sequencing.

Results

We identified three variants of NKX2-5: NM_004387.4:c.63A>G at exon 1, NM_004387.4:c.413G>A, and NM_004387.4:c.561G>C at exon 2. The first variant is commonly found (85.6%) and benign. The last two variants are heterozygous at the same locus. These variants are rare (3.1%) and novel. Interestingly, these variants were discovered in familial atrial septal defects with a spectrum of arrhythmia and severe pulmonary hypertension.

Conclusion

Our study is the first report of the NKX2-5 variant in ASD patients in the Southeast Asian population, including a novel heterozygous variant: NM_004387.4:c.413G>A and NM_004387.4:c.561G>C. These variants might contribute to familial ASD risk with arrhythmia and severe pulmonary hypertension. Functional studies are necessary to prove our findings.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12920-022-01242-8.

The role of NKX2-5 gene polymorphisms in congenital heart disease (CHD): a systematic review and meta-analysis

BACKGROUND

The gene NKX2-5 is a key transcription factor that plays an essential role in normal cardiac development. Although some recent studies have studied the role of polymorphisms in the NKX2-5 gene in congenital heart diseases (CHDs), the results were not consistent and remained uncertain. Therefore, we conduct a review of literature and investigate the association of genetic polymorphisms with CHDs.

RESULTS

We selected seventeen studies regarding the association of NKX2-5 gene rs2277923 polymorphism with CHDs. Overall, in all the tested genetic models, the 63A > G polymorphism was not significantly associated with increased congenital heart defects risk. We used pooled odds ratios (OR) to calculate the association of CHDs with rs2277923 including allelic model: OR 1.00, 95% CI 0.82-1.21; homozygote model: OR 0.95, 95%CI 0.68-1.33, recessive model: OR 0.89 CI 0.70-1.13, heterozygote model: OR: 1.09, 95%CI 0.87-1.37, dominant model: OR 1.08 CI 0.82-1.42 and overdominant model: OR 1.17 CI 1.01-1.35. In addition, our analysis suggests that no publication bias exists in this meta-analysis.

CONCLUSIONS

Our findings suggested that 63A > G polymorphism in the NKX2-5 gene was not significantly associated with congenital heart defects. However, in the future, more studies with increased sample size are required that may provide us more definite conclusions.