Article Text

Comprehensive mutation scanning of KCNQ1 in 111 Han Chinese patients with lone atrial fibrillation
  1. Lin Y Chen1,6,
  2. June M Goh2,
  3. Raymond C Wong3,
  4. Li-Fern Hsu4,
  5. David Foo5,
  6. David G Benditt1,
  7. Lieng H Ling6,
  8. Chew K Heng2
  1. 1The Department of Medicine, Cardiovascular Division (Cardiac Arrhythmia Centre), University of Minnesota, Minneapolis, Minnesota, USA
  2. 2Department of Paediatrics, National University of Singapore, Singapore
  3. 3Cardiac Department, National University Hospital, Singapore
  4. 4Department of Cardiology, National Heart Centre, Singapore
  5. 5Department of Cardiology, Tan Tock Seng Hospital, Singapore
  6. 6Department of Medicine, Cardiovascular Division, National University of Singapore, Singapore
  1. Correspondence to Dr Lin Y Chen, Department of Medicine, Cardiovascular Division, University of Minnesota Medical School, 420 Delaware Street SE, MMC 508, Minneapolis, MN 55455, USA; chenx484{at}


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.

  • Atrial fibrillation
  • potassium channel
  • KCNQ1
  • genetics

Statistics from


  • Funding National Medical Research Council of Singapore (NMRC/1141/2007).

  • Competing interests None.

  • Patient consent Obtained.

  • Ethics approval Ethics approval was provided by the National University of Singapore Institutional Review Board.

  • Provenance and peer review Not commissioned; not externally peer reviewed.

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.