OBJECTIVETo have a better understanding of genetic contributions to the development of obstructive sleep apnea hypopnea syndrome (OSAHS) by reviewing studies on its genetic basis.

DATA SOURCESA comprehensive search of the PubMed literature without restriction on the publication date was carried out using terms "obstructive sleep apnea" and "candidate genes" or "genetics".

STUDY SELECTIONArticles were selected if they were an original research paper or meta analysis of the genetic factors of OSAHS.

RESULTSFour intermediate phenotypes were described and several candidate genes that may determine the expression and severity of OSAHS were reviewed.

CONCLUSIONMultiple gene-gene interactions occurring in genes that affect obesity, craniofacial structure, ventilator control and asleep-awake pattern may influence the expression of OSAHS in a suitable environment.