Association study of serotonin transporter gene polymorphisms with obstructive sleep apnea syndrome in Chinese Han population.
BACKGROUND
Since the serotonin (5-HT) is associated with circadian rhythm and breathing regulation, the serotonin transporter (5-HTT), which plays an important role in serotoninergic transmission, might be a strong candidate gene in the pathogenesis of obstructive sleep apnea syndrome (OSAS).


OBJECTIVE
To investigate the association of 5-HTT gene polymorphisms with OSAS and clinical characteristics.


METHODS
We genotyped the 5-HTT gene linked polymorphic region (5-HTTLPR) and a variable number of tandem repeats at intron 2 (STin2.VNTR) in 254 OSAS patients and 338 healthy controls in Chinese Han population.


RESULTS
In total sample, the 10-repeat allele of STin2.VNTR was significantly associated with OSAS (P = 0.007, OR = 1.72, 95% CI = 1.15-2.58), but no association was found in 5-HTTLPR. In male subjects, both polymorphisms showed significant association with OSAS (Allele L: P = 0.005, OR = 1.44, 95% CI = 1.11 to 1.87; Allele 10: P = 0.002, OR= 1.94, 95% CI = 1.26 to 3.00). Two haplotypes, S-12 and L-10, constructed by the above polymorphisms also revealed significant associations with OSAS (global P-values were 0.020 for total sample and 0.0006 for male subjects, respectively). Male patients carrying the haplotype S-12 showed a significantly lower apnea / hypopnea index (AHI), depressive factor, plasma 5-HT level and 5-hydroxyindolacetic acid (5-HIAA) levels, but higher episodic memory, when compared with non-S-12 carriers (P < 0.05). However, no significant differences were found in excessive daytime sleepiness or other psychological function across haplotype carriers (P > 0.05).


CONCLUSIONS
These findings support that 5-HTT gene may be involved in susceptibility to OSAS, especially with sex-dependent effect.
Yue
Weihua
W
Mental Health Institute, the Second Xiangya Hospital, Central South University, Changsha, PR China.
Liu
Huiguo
H
Zhang
Jishui
J
Zhang
Xianghui
X
Wang
Xiaoping
X
Liu
Tieqiao
T
Liu
Pozi
P
Hao
Wei
W
D000483:Alleles; D044466:Asian People / Q000706:statistics & numerical data*; D015992:Body Mass Index; D002681:China / Q000453:epidemiology; D002940:Circadian Rhythm / Q000502:physiology; D017931:DNA Primers / Q000235:genetics; D003866:Depressive Disorder / Q000175:diagnosis / Q000453:epidemiology / Q000523:psychology; D004569:Electroencephalography; D005006:Ethnicity / Q000706:statistics & numerical data*; D005260:Female; D005838:Genotype; D006239:Haplotypes; D006801:Humans; D008297:Male; D008875:Middle Aged; D011110:Polymorphism, Genetic / Q000235:genetics*; D017286:Polysomnography; D050486:Serotonin Plasma Membrane Transport Proteins / Q000235:genetics*; D012720:Severity of Illness Index; D020181:Sleep Apnea, Obstructive / Q000175:diagnosis / Q000208:ethnology* / Q000235:genetics*
D017931:DNA Primers; C493230:SLC6A4 protein, human; D050486:Serotonin Plasma Membrane Transport Proteins