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This Article Full Text Full Text (PDF) All Versions of this Article: 295/5/H2156    most recent 00662.2008v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Google Scholar Articles by Viola, A. U. Articles by Dijk, D.-J. PubMed PubMed Citation Articles by Viola, A. U. Articles by Dijk, D.-J.

PER3 polymorphism and cardiac autonomic control: effects of sleep debt and circadian phase

Surrey Sleep Research Centre, Faculty of Health and Medical Sciences, University of Surrey, Guildford, United Kingdom

Submitted 24 June 2008 ; accepted in final form 26 September 2008

A variable number tandem repeat polymorphism in the coding region of the circadian clock PERIOD3 (PER3) gene has been shown to affect sleep. Because circadian rhythms and sleep are known to modulate sympathovagal balance, we investigated whether homozygosity for this PER3 polymorphism is associated with changes in autonomic nervous system (ANS) activity during sleep and wakefulness at baseline and after sleep deprivation. Twenty-two healthy participants were selected according to their PER3 genotype. ANS activity, evaluated by heart rate (HR) and HR variability (HRV) indexes, was quantified during baseline sleep, a 40-h period of wakefulness, and recovery sleep. Sleep deprivation induced an increase in slow-wave sleep (SWS), a decrease in the global variability, and an unbalance of the ANS with a loss of parasympathetic predominance and an increase in sympathetic activity. Individuals homozygous for the longer allele (PER3^5/5) had more SWS, an elevated sympathetic predominance, and a reduction of parasympathetic activity compared with PER3^4/4, in particular during baseline sleep. The effects of genotype were strongest during non-rapid eye movement (NREM) sleep and absent or much smaller during REM sleep. The NREM-REM cycle-dependent modulation of the low frequency-to-(low frequency + high frequency) ratio was diminished in PER3^5/5 individuals. Circadian phase modulated HR and HRV, but no interaction with genotype was observed. In conclusion, the PER3 polymorphism affects the sympathovagal balance in cardiac control in NREM sleep similar to the effect of sleep deprivation.

clock gene; autonomic nervous system; cardiovascular risk; slow wave activity