Autosomal random monoallelic expression in development and disease.

Autosomal random monoallelic expression (aRME) occurs when either one or both parental alleles of autosomal genes are stochastically expressed in individual cells, leading to allelic heterogeneity within an isogenic population. With growing evidence supporting the observation of aRME across different biological systems, understanding its functional relevance has become imperative. Recent studies have begun to elucidate the role of aRME in development, diseases, and evolution. Notably, aRME potentially contributes to cellular plasticity and cell-fate transitions during early development, while also influencing phenotypic variability, adaptability, and disease outcomes across immune, cardiac, neuronal, and age-associated diseases. In parallel, ongoing studies continue to refine our understanding of the molecular mechanisms governing aRME. In this review, we elaborate on these aspects of aRME.