Introduction
The CRYAB gene encodes the protein Alpha-B-crystallin, or αB-crystallin,
a protein belonging to the small heat shock family of proteins that has
been linked to normal cardiac homeostasis as well as cardiomyopathies,
among other diseases 1. CRYAB, the causal gene, is 3.2
kilobases long and situated on chromosome 11 2.
Although its role as a molecular chaperone for desmin is well
established, it also engages in interactions with a diverse range of
other proteins 1.
Mutations in the CRYAB gene have been associated with congenital
cataracts, myopathies, neurodegenerative diseases, and besides with
hypertrophic cardiomyopathy (HCM), and less commonly with dilated
cardiomyopathy (DCM) and restrictive cardiomyopathy (RCM)1,3-5.
However, the CRYAB association with DCM has recently emerged in the last
decade, which is why it may not be included in the list of genetic
mutations associated with DCM according to the most recent guidelines of
the European Society of Cardiology (ESC) and some reviews in recent
literature. However, increasing emerging observational evidence suggests
an association with DCM. Below we describe the case of a patient who
developed DCM whit restrictive physiology secondary to a heterozygous
mutation of the CRYAB gene.