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Open Access

Rhythm disorder alleles

  • Jonathan B Weitzman
Genome Biology20012:spotlight-20010424-02

Published: 24 April 2001


Sequence VariationCircadian RhythmGenetic PolymorphismAmino Acid ChangeClock Gene

The genes that regulate circadian rhythms have been genetically characterized in flies and mice. In the April issue of EMBO Reports, Ebisawa et al. describe a screen for genetic polymorphisms associated with human circadian rhythm disorders (EMBO Reports 2001, 2:342-346). They performed a PCR-based analysis of the human period3 gene (hPer3), a homolog of a Drosophila clock gene, and identified 20 sequence variations, of which six predicted amino acid changes. Ebisawa et al. defined four haplotypes for the hPer3 gene. Screening a group of 48 patients with delayed sleep phase syndrome (DSPS), they discovered that the H4 haplotype was associated with DSPS in approx 15% of cases. The authors speculate that a structural polymorphism may affect hPer3 phosphorylation, causing DSPS susceptibility.


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© BioMed Central Ltd 2001