Evaluation of a circadian rhythm gene (PER3) VNTR variant in Turkish athletes

Abstract

Objective

Circadian rhythmicity has been shown to contribute to the regulation of key physiological and cognitive processes related to performance. The period homolog 3 (PER3) is expressed in a circadian pattern in the suprachiasmatic nucleus. Therefore, in this study, we aimed to evaluate the role of the variable tandem repeat (VNTR) variant of the PER3 gene in athletic performance in the Turkish population.

Methods

This study included 223 subjects, which consisted of 123 athletes and 100 sedentary controls. Blood samples were drawn from all subjects. DNA was extracted from whole-blood samples. The PER3 VNTR variant was genotyped using the polymerase chain reaction-restriction method (PCR). The results of the analyses were evaluated for statistical significance.

Results

The mean ages of athletes and controls were 22 ± 2.814 and 23 ± 3.561, respectively. Endurance athletes in the group were 21.1%, and sprint athletes were 78.9%. There was no statistical significance in terms of PER3 VNTR genotype distribution or allele frequency. In the recessive model, a statistically significant association was observed when the athletes were compared with the controls according to 4/4 + 4/5 versus 5/5 genotype (p = 0.020).

Conclusion

In this case-control study, for the first time in our country, we obtained findings suggesting that the PER3 VNTR variant may affect sports performance in the Turkish population. Results need to be replicated in different ethnic and larger samples.

Keywords:

• Circadian rhythm
• elite athlete
• PER3 gene
• VNTR
• performance

Acknowledgments

We thank all of the patients and their parents who contributed to the study. The authors received no financial support for the research, authorship, and/or publication of this article.

Author contributions

S.U. and S.Y. conceived the idea, designed it and drafted the manuscript. T.A. collected and analyzed the data. SU prepared figures. ET and EY contributed to writing the manuscript. E.Y. edited the article. All authors checked and arranged on the final version of the manuscript and agreed to be accountable for all aspects of the work.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The author(s) reported there is no funding associated with the work featured in this article.