In the present study, rare mutation (c.-781C>G) in 5′UTR of AHDC1 was found in severe OSA patients, and this rare mutation could affect expression of AHDC1. Therefore, we assumed that the mutations in AHDC1 may affect the expression of AHDC1 and lead to sleep apnea. This evidence concerns the gene AHDC1 and obstructive sleep apnea syndrome.