Background: Conflicting results regarding associations between single nucleotide polymorphisms (SNPs) in IRS1, ACE, APOE, PPARG, MTHFR, 5HT2AR, BDNF, and FTO genes and obstructive sleep apnea have been reported in previous studies.
Objective: To assess pleiotropic associations between these gene polymorphisms that are commonly being studied in a nutrigenetic test and sleep apnea.
Methods: One hundred and nine subjects of Caucasian origin who have performed a commercially available nutrigenetic test that includes the aforementioned polymorphisms were divided into two groups depending on the results of their Sleep Apnea Clinical Score (SACS ≤ 15 or > 15). Statistical significant differences in the prevalence of the polymorphisms under study between the groups were assessed with the Chi-squared test. Possible associations of the polymorphisms with SACS and BMI were further evaluated with logistic regression analyses.
Results: From the polymorphisms studied, only variant rs9939609 in the FTO gene was more prevalent in people with high sleep apnea clinical score (χ2 = 7.1, P = 0.029). However, this association was attenuated after adjustment for body mass index (OR = 0.653, P = 0.178).
Conclusion: We failed to confirm previously reported associations between the majority of the studied polymorphisms and sleep apnea. Body weight seems to be an important cofounding factor that needs to be accounted for, when genetic association studies are performed for sleep apnea.
Keywords: Gene polymorphisms; Nutrigenetics; Sleep apnea.