Furthermore, in a study of 164 patients with severe OSA and 171 patients without OSA, 2 genetic variants of the TASK-1 gene were a risk factor in obese patients for developing severe OSA versus no OSA.100 Also, it has been reported that chronic intermittent hypoxia (CIH) enhances inhibition of carotid body TASK channels101,102; this may help explain the heightened carotid body responsivity to acute hypoxia seen under CIH. This evidence concerns the gene KCNK3 and obstructive sleep apnea syndrome.