Association of the Length Polymorphism in the Human Per3 Gene with the Delayed Sleep-Phase Syndrome: Does Latitude Have an Influence Upon It?

• DOI: 10.1093/sleep/28.1.29
• Publication Date: 2017-02-05T16:50:57Z
• Authors: Sergio Tufik; Alberto Remesar L...; Fernando Mazzilli...; Nelson A. M. Lemos; Ana Amélia Benedi...; Danyella Silva Pe...; Anna Ligia Korczak; Mario Pedrazzoli; Vânia D'Almeida
• Keywords: Adult; Male; Polymorphism, Genetic; Genotype; Geography; Nuclear Proteins; Period Circadian Proteins; Severity of Illness Index; Circadian Rhythm; 03 medical and health sciences; 0302 clinical medicine; Gene Frequency; Sleep Disorders, Circadian Rhythm; Surveys and Questionnaires; Humans; Female; Brazil; Transcription Factors

The objective of this study is to analyze the influence of a previously reported hPer3 gene-length polymorphism in the delayed sleep-phase syndrome and in morningness-eveningness tendencies at low latitudes in the southern hemisphere.We have genotyped a length polymorphism in the hPer3 gene characterized by a short repeat allele (4-repeat) and a long repeat allele (5-repeat).Seventeen patients with delayed sleep-phase syndrome; 156 volunteers chosen according to Horne-Ostberg questionnaire to have morning, intermediate, or evening preference; and 110 volunteers with no Horne-Ostberg score as a sample of the general population.We have found a higher frequency of 5-repeat allele in the delayed sleep-phase syndrome group and an association of this polymorphism with diurnal preference.Our results suggest that latitude has a role in the influence of hPer3 gene polymorphism on delayed sleep-phase syndrome and confirm previous data showing its association with morningness-eveningness tendencies.