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Lack of association between PER3 variable number tandem repeat and circadian rhythm sleep-wake disorders
Akiko Hida1, Shingo Kitamura1, Hiroshi Kadotani2
11Department of Sleep-Wake Disorders, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo, 187-8553 Japan.
Abstract:
Circadian rhythm sleep-wake disorders (CRSWDs) are characterized by disturbed sleep-wake patterns. We genotyped a PER3 variable number tandem repeat (VNTR) in 248 CRSWD individuals and 925 controls and found no significant association between the VNTR and CRSWDs or morningness-eveningness (diurnal) preferences in the Japanese population. Although the VNTR has been associated with circadian and sleep phenotypes in some other populations, the polymorphism may not be a universal genetic marker.
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