ULK1 and obstructive sleep apnea syndrome: ULK1 gene expression was decreased in OSA patients versus PS subjects (0.73 ± 0.86 versus 1.22 ± 1.25 fold change, adjusted p = 0.027, Fig. 2F), and positively correlated with minimum SaO2 during total sleep time (R = 0.276, p = 0.029, Fig. 2G).