The genetics of obstructive sleep apnoea.
OBJECTIVE
Obstructive sleep apnoea syndrome (OSAS) is a highly prevalent disorder associated with reduced quality of life and adverse cardiovascular and metabolic sequelae. Recent years have seen an intensification of the research effort to establish the genetic contribution to the development of OSAS and its sequelae. This review explores emerging evidence in this field.


RESULTS
A genetic basis for sleep-disordered breathing has been demonstrated for discrete disorders such as Treacher-Collins and Down syndromes, but the picture is less clear in so-called idiopathic OSAS. A degree of heritability appears likely in some of the intermediate phenotypes that lead to OSAS, particularly craniofacial morphology. However, only sparse and often contradictory evidence exists regarding the role of specific polymorphisms in causing OSAS in the general population. Similarly, investigations of the cardiovascular sequelae of OSAS have in general failed to consistently find single causative genetic mutations. Nonetheless, evidence suggests a role for tumour necrosis factor-α polymorphisms in particular, and large-scale family studies have suggested shared pathogenetic pathways for the development of obesity and OSAS.


CONCLUSIONS
As with other common disorders, OSAS is likely to result from multiple gene-gene interactions occurring in a suitable environment. The application of modern genetic investigative techniques, such as genome-wide association studies, may facilitate new discoveries in this field.
Kent
Brian D
BD
Pulmonary and Sleep Disorders Unit, St Vincent's University Hospital, Dublin, Ireland.
Ryan
Silke
S
McNicholas
Walter T
WT
D002318:Cardiovascular Diseases / Q000453:epidemiology; D006801:Humans; D009154:Mutation / Q000235:genetics*; D011110:Polymorphism, Genetic / Q000235:genetics*; D012307:Risk Factors; D020181:Sleep Apnea, Obstructive / Q000235:genetics*; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics
D014409:Tumor Necrosis Factor-alpha