RESUMEN
Long QT syndrome (LQTS), a rare cardiac condition that can lead to sudden death, is highly prevalent in First Nations communities of northern British Columbia. In the Gitxsan community of 5500, an estimated 1 in 125 individuals are affected, primarily due to the novel pathogenic variant p.V205M in KCNQ1. Over the past decade, more than 800 Gitxsan individuals received genetic testing and counseling for LQTS through a community-based study. Despite the substantial research characterizing the biological underpinnings of LQTS, there are few studies exploring the lived experiences of families with LQTS, especially those of Indigenous peoples. The goal of this study was to gain a greater understanding of the impact of the genetic confirmation of LQTS in this community, and the impact the condition has on individuals, their families, and the community. A qualitative study was developed in consultation with a local research advisory board and a Talking Circle, a traditional Indigenous format for discussion, was held. Four people who belonged to the same kindred group attended the Talking Circle. This article presents the multigenerational impact that LQTS and genetic diagnosis have through the reflections of one Gitxsan family. LQTS affects identity and family relationships, including those between parents and children, siblings, and even extended family members. Laughter and humor played an important part in coping. The role of family relationships for this Gitxsan family was seen to be critical in managing an LQTS diagnosis. This multigenerational perspective provides key insights into family structure and dynamics which can inform genetic counseling and clinical care. As cultural safety is experienced and therefore defined by the person receiving services, listening to the perspectives and preferences of Indigenous peoples is essential to the delivery of culturally informed care.
RESUMEN
The ANK2 gene encodes for ankyrin-B (ANKB), one of 3 members of the ankyrin family of proteins, whose name is derived from the Greek word for anchor. ANKB was originally identified in the brain (B denotes "brain") but has become most widely known for its role in cardiomyocytes as a scaffolding protein for ion channels and transporters, as well as an interacting protein for structural and signaling proteins. Certain loss-of-function ANK2 variants are associated with a primarily cardiac-presenting autosomal-dominant condition with incomplete penetrance and variable expressivity characterized by a predisposition to supraventricular and ventricular arrhythmias, arrhythmogenic cardiomyopathy, congenital and adult-onset structural heart disease, and sudden death. Another independent group of ANK2 variants are associated with increased risk for distinct neurological phenotypes, including epilepsy and autism spectrum disorders. The mechanisms underlying ANKB's roles in cells in health and disease are not fully understood; however, several clues from a range of molecular and cell biological studies have emerged. Notably, ANKB exhibits several isoforms that have different cell-type-, tissue-, and developmental stage- expression profiles. Given the conservation within ankyrins across evolution, model organism studies have enabled the discovery of several ankyrin roles that could shed important light on ANKB protein-protein interactions in heart and brain cells related to the regulation of cellular polarity, organization, calcium homeostasis, and glucose and fat metabolism. Along with this accumulation of evidence suggesting a diversity of important ANKB cellular functions, there is an on-going debate on the role of ANKB in disease. We currently have limited understanding of how these cellular functions link to disease risk. To this end, this review will examine evidence for the cellular roles of ANKB and the potential contribution of ANKB functional variants to disease risk and presentation. This contribution will highlight the impact of ANKB dysfunction on cardiac and neuronal cells and the significance of understanding the role of ANKB variants in disease.