Genetic Factors in Sleep Disorders: What Are the Roles of Genetic Factors in the Pathogenesis of Sleep Disorders?

Abstract

Most normal sleep traits and sleep disorders have a familial aggregation, suggesting significant effects of genetic factors. Obstructive sleep apnea (OSA) is a common and complex sleep disorder and has heritability. A recent genome-wide association study (GWAS) identified some genetic risks for OSA with genome-wide levels of significance for the first time. Congenital central hypoventilation syndrome has causative mutations in the paired-like homeobox 2B (PHOX2B) gene, and its phenotypes are associated with PHOX2B genotypes. GWASs have revealed several genetic variances for restless legs syndrome (RLS), whereas these variances have left most of the heritability in RLS unexplained. Narcolepsy is strongly associated with HLA DQ-B1*06:02, and the results of GWASs indicate an autoimmune pathogenesis of narcolepsy. Insomnia has significant heritability, and findings of GWASs have suggested common genetic predispositions with psychiatric disorders and sleep reactivity. Familial fatal insomnia is an autosomal-dominant genetic disorder caused by a mutation in the prion protein (PRNP) gene. Although advances in genetics have resulted in identification of genetic causes of some sleep disorders, further studies are required to elucidate the cellular and molecular mechanisms from genetic risks to clinical manifestations.