Circadian Rhythm Genes and Sleep Disorders in an Open Population of Men Aged 25–64 Years (an Epidemiological Study under the WHO MONICA-Psychosocial Program)

Objectives. To study the influences of polymorphisms of genes encoding circadian rhythm proteins (CLOCK, BMAL1, PER2, and NPAS2) on sleep disorders in an open population of men aged 25–64 years. Materials and methods. General examination was carried out using the standard methods included in the World Health Organization (WHO) “MONICA-psychosocial (MOPSY)” program. Sleep disorders were studied using the standard Jenkins questionnaire. Genotyping in terms of polymorphisms of the CLOCK, BMAL1, PER2, and NPAS2 genes was performed. Results. Carriers of the rs2412646 C/T genotype of the CLOCK gene felt that their sleep was “satisfactory” or “bad” more often than other subjects. Carriers of the rs2278749 C/T genotype of the BMAL1 gene more often experienced disturbing dreams and woke up tired and exhausted. Carriers of the rs934945 A/A genotype of the PER2 gene more often (25%) woke up two or more times per night, generally from 4–7 times a week. In the population, the rs4851377 C/T and T/T genotypes of the NPAS2 gene were significantly more common in individuals getting 7 h of sleep (50% and 53.3%, respectively). Conclusions. Associations between certain polymorphisms of the CLOCK, BMAL1, PER2, and NPAS2 genes with sleep disorders were found.