Huq, Aamira J

Pertile, MD

Davis, AM

Landon, H

James, PA

Kline, CF

Vohra, J

Mohler, PJ

Delatycki, Martin B

2017-06

BACKGROUND: Cardiac rhythm abnormalities are a leading cause of morbidity and mortality in developed countries. Loss-of-function variants in the ANK2 gene can cause a variety of cardiac rhythm abnormalities including sinus node dysfunction, atrial fibrillation and ventricular arrhythmias (called the "ankyrin-B syndrome"). ANK2 encodes ankyrin-B, a molecule critical for the membrane targeting of key cardiac ion channels, transporters, and signalling proteins. METHODS AND RESULTS: Here, we describe a family with a reciprocal chromosomal translocation between chromosomes 4q25 and 9q26 that transects the ANK2 gene on chromosome 4 resulting in loss-of-function of ankyrin-B. Select family members with ankyrin-B haploinsufficiency due to the translocation displayed clinical features of ankyrin-B syndrome. Furthermore, evaluation of primary lymphoblasts from a carrier of the translocation showed altered levels of ankyrin-B as well as a reduced expression of downstream ankyrin-binding partners. CONCLUSIONS: Thus, our data conclude that, similar to previously described ANK2 loss-of-function "point mutations", large chromosomal translocations resulting in ANK2 haploinsufficiency are sufficient to cause the human cardiac ankyrin-B syndrome. The unexpected ascertainment of ANK2 dysfunction via the discovery of a chromosomal translocation in this family, the determination of the familial phenotype, as well as the complexities in formulating screening and treatment strategies are discussed.

Heart, Lung and Circulation 2017; 26(6): 612-618

Heart, Lung and Circulation

https://ahro.austin.org.au/austinjspui/handle/1/16557

ANK2

Ankyrin-B

Ankyrin-B syndrome

Cardiac arrhythmia

Chromosome 4 translocation

Long QT syndrome type 4

A novel mechanism for human cardiac Ankyrin-B syndrome due to reciprocal chromosomal translocation

Journal Article