Angiotensin-converting enzyme gene polymorphism in north Indian population with obstructive sleep apnea.
BACKGROUND
A deletion of 287-bp Alu repeat of angiotensin-converting enzyme (ACE) insertion/deletion (I/D) gene is associated with hypertension.


OBJECTIVE
The aim of this study is to determine the frequency of ACE (I/D) polymorphism in patients with obstructive sleep apnea (OSA).


METHODS
Genotyping of ACE (I/D) gene polymorphism and estimation of serum angiotensin-converting enzyme (SACE) activity were done in 813 subjects who underwent polysomnography. Of these, 395 were apneics and 418 were non-apneics.


RESULTS
The frequencies of II genotype (OR = 1.8, 95 % CI 1.26-2.60, p = 0.001) and I allele (OR = 1.4, 95 % CI 1.13-1.69, p = 0.001) of ACE gene were found to be significantly increased in patients with OSA as compared to patients without OSA. Frequency of II genotype was significantly decreased (OR = 0.46, 95 % CI 0.28-0.77, p = 0.003) in OSA patients with hypertension. In contrast, the frequencies of ID (OR = 1.80, 95 % CI 1.08-2.99, p = 0.024) and DD genotypes (OR = 2.15, 95 % CI 1.30-3.57, p = 0.003) were significantly increased in this group. The activity of SACE was significantly decreased in the apneic group as compared to the non-apneic group (OR = 0.99, 95 % CI 0.98-1.00, p = 0.04).


CONCLUSIONS
The findings suggest that II genotype confers susceptibility towards development of OSA whereas DD genotype confers susceptibility towards hypertension irrespective of OSA.
Department of Medicine, All India Institute of Medical Sciences, New Delhi 110029, India.
H K
HK
Mishra
S K
SK
Sharma
V
V
Sreenivas
D000328:Adult; D000483:Alleles; D020087:Alu Elements / Q000235:genetics*; D003430:Cross-Sectional Studies; D005260:Female; D005500:Follow-Up Studies; D005787:Gene Frequency / Q000235:genetics; D005838:Genotype; D006801:Humans; D006973:Hypertension / Q000235:genetics*; D054643:INDEL Mutation / Q000235:genetics*; D007194:India; D008297:Male; D008875:Middle Aged; D007703:Peptidyl-Dipeptidase A / Q000097:blood / Q000235:genetics*; D011110:Polymorphism, Genetic / Q000235:genetics*; D017286:Polysomnography; D020181:Sleep Apnea, Obstructive / Q000453:epidemiology / Q000235:genetics*
D007703:Peptidyl-Dipeptidase A