Comprehensive mutation scanning of KCNQ1 in 111 Han Chinese patients with lone atrial fibrillation.

ABSTRACT: OBJECTIVE:To determine the extent to which genetic variation in the potassium channel gene KCNQ1 causes atrial fibrillation (AF). DESIGN:Case-control study. SETTING:National University Hospital, Singapore. PATIENTS:Han Chinese patients (n=111) with lone AF (onset <60?years and lacking risk factors) and 265 Han Chinese controls. INTERVENTIONS:Blood draw, 12-lead electrocardiogram and transthoracic echocardiogram were performed on patients with AF at enrolment. MAIN OUTCOME MEASURES:DNA sequence variants in the coding region and exon-intron boundaries of KCNQ1 as detected by direct sequencing. RESULTS:Four previously reported coding variants were identified: I145I, S546S, P448R and G643S. An additional 19 non-coding variants were identified, nine of which are newly reported. None were predicted to create a cryptic splicing site. The allele frequencies of the two non-synonymous variants did not differ significantly in the AF cases compared with 265 Han Chinese controls (P448R: 10.8% in cases vs 8.6% in controls, p=0.41; G643S: 1.4% in cases vs 0.8% in controls, p=0.43). CONCLUSIONS:Comprehensive mutation scanning of KCNQ1 did not identify novel pathogenic mutations or risk-conferring polymorphisms. As in Caucasians, genetic variation in KCNQ1 is not a common cause of AF in Han Chinese. Routine genetic testing of KCNQ1 for AF is, therefore, not warranted.

SUBMITTER: Chen LY 

PROVIDER: S-EPMC4898533 | biostudies-literature | 2010

REPOSITORIES: biostudies-literature