Mean DNA methylation levels over − 172, − 157, − 153, − 141, − 134, and − 118 CpG sites of the LC3B gene (3.93 ± 0.94 versus 3.24 ± 0.82%, adjusted p = 0.002, Fig. 3A) and mean DNA methylation levels over − 53, − 46, − 44, − 42, and − 37 CpG sites of the LC3B gene (2.5 ± 0.89 versus 1.97 ± 0.62%, adjusted p = 0.033, Fig. 3B) were both increased in OSA patients versus PS subjects, and the former was positive correlated with AHI (R = 0.262, p = 0.017, Fig. 3C). This evidence concerns the gene MAP1LC3B and obstructive sleep apnea syndrome.