ABSTRACT
Objectives To investigate the relationship between single nucleotide polymorphism (SNP)H558R in SCN5A gene and chronic Keshan disease (KSD) complicated with hypertension,and the relationship between H558R and occurrence of arrythmia in chronic KSD complicated with hypertension.MethodsThirty nine patients with chronic KSD complicated with hypertension and 63 geographical region matched hypertension control subjects were recruited in our study in Fuyu county,Qiqihaer city,Heilongjiang province between 2006 and 2010.H558R polymorphism in case and control groups was genotyped using the polymerase chain reaction single-strand conformation polymorphism(PCR-SSCP) and sequenced,and electrocardiography(ECG) characteristics were examined in the two groups.Case-control study analytical methods were applied to analyze the relationship between H558R and chronic KSD complicated with hypertension,and the relationship between H558R and occurrence of arrythmia in chronic KSD patients complicated with hypertension.Results Subjects of genotype 558 TC in the case group had a decreased risk of chronic KSD complicated with hypertension with odds ratio of 0.288[95％ confidence interval (CI):0.104 - 0.794],and subjects of genotype TC in chronic KSD complicated hypertension patients had a decreased risk of QRS prolongation with odds ratio of 0.061 (95％CI:0.006 - 0.612).Conclusions Polymorphism H558R in SCN5A gene may be a predisposition factor of chronic KSD complicated with hypertension and occurrence of arrythmia in chronic KSD complicated with hypertension.
ABSTRACT
98% amino acid identity.There are 28 different amino acids between them,with 7 of which locating in the region encoded by exon6A or exon6.Alternative splicing of exon18 was not found in the gene cloning of human brain Nav1.5/SCN5A,which was different from human heart Nav1.5/SCN5A,but a novel alternative splicing lacking exon24 was first found.The two variants were detected in similar ratio in brain,but they were proved to relate to age development in heart tissue.The exon24 of human Nav1.5/SCN5A has 54 nucleotides,encoding 30 amino acid residues,and are located in human chromosome 3P21.This alternative splicing was also found in other tissues other than heart and brain.The expression pattern of the two variants in different tissues was different when detected by competitive PCR method and it was also changing with age development.Furthermore,Nav1.5/SCN5A mRNA was detected in 16 different tissue types of Wistar rats(P80) by reverse polymerase chain reaction(RT-PCR) .These results suggest that Nav1.5 Na+ channels in human brain are encoded by new variants of Nav1.5/SCN5A and its mRAN is more widely expressed than previously thought.The study is useful for making further investigation in the functional analysis of Nav1.5 Na+ channels in different tissues.