LACC1 gene mutation in three sisters with polyarthritis without systemic features

Abstract

Correspondence to Dr Deepti Suri, Pediatric Allergy Immunology, Advanced Pediatrics Centre, Post Graduate Institute of Medical Education and Research, Chandigarh, 160012, India; [email protected] Juvenile idiopathic arthritis (JIA) refers to a group of disorders characterised by wide phenotypic diversity and genetic heterogeneity. Disordered immune response to an environmental trigger in a genetically predisposed individual is the proposed mechanism for most JIA subtypes.1 2 There are emerging reports on new gene locus being identified especially in families with many affected members.3 4 We report three sisters with polyarthritis who were identified to have causative variant in Laccase domain containing one (LACC1) gene by whole exome sequencing. Over the next 2 years, multiple joint involvement, pain, deformities and contractures resulted in limitation of normal routine activities, and the children were bed bound. LACC1 is involved in inflammasome activation, fatty acid oxidation and production of reactive oxygen species by nicotinamide adenine dinucleotide phosphate hydrogen (NADPH) oxidase and mitochondrial pathways.9 10 Mutation in this gene has been linked to JIA, inflammatory bowel disease and Behcet’s disease.4 11 12 JIA is mostly sporadic and familial aggregation is uncommon.