Article

Frequency of distribution of leptin receptor gene polymorphism in obstructive sleep apnea patients.

Department of Laboratory Diagnostics and Clinical Immunology of the Developmental Age, Warsaw Medical University, Warsaw, Poland.
Journal of physiology and pharmacology: an official journal of the Polish Physiological Society (impact factor: 2.27). 12/2007; 58 Suppl 5(Pt 2):551-61. pp.551-61
Source: PubMed

ABSTRACT Leptin is an adipocyte-derived hormone regulating energy homeostasis and body weight. Leptin concentration is increased in patients with the obstructive sleep apnea syndrome (OSAS). Leptin receptor (LEPR) is a single transmembrane protein belonging to the superfamily of cytokine receptors related by a structure to the hemopoietin receptor family. The aim of the present study was to evaluate the frequency of distribution of leptin receptor gene polymorphism GLN223ARG in OSAS patients compared with healthy controls. The examined group included 179 subjects: 102 OSAS patients (74 men and 28 women) and 77 non-apneic controls (39 men and 38 women). Genomic DNA was isolated with the use of a column method and genotyping of DNA sequence variation was carried out by restriction enzyme analysis of PCR-amplified DNA. The results revealed a significant correlation between the polymorphism of LEPR and OSAS. Carriers of Arg allele in homozygotic genotype Arg/Arg and heterozygotic genotype Gln/Arg were more often obese and developed OSAS than the group of carriers of homozygotic Gln/Gln genotype. This tendency was observed in the whole examined population and in the group of obese women. We also found the highest levels of total cholesterol, LDL, HDL, and triglycerides in the group of homozygotic Arg/Arg genotype carriers, lower in heterozygotic Gln/Arg genotype carriers, and the lowest in the group of persons carring homozygotic Gln/Gln genotype. The presence of Arg allel seems linked to a higher risk of obesity and higher lipid levels in OSAS patients. OSAS may have a strong genetic basis due to the effects from a variety of genes including those for leptin receptor.

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Keywords

102 OSAS patients
 
77 non-apneic controls
 
cytokine receptors
 
examined group
 
hemopoietin receptor family
 
heterozygotic genotype Gln/Arg
 
heterozygotic Gln/Arg genotype carriers
 
higher lipid levels
 
homozygotic Arg/Arg genotype carriers
 
homozygotic genotype Arg/Arg
 
homozygotic Gln/Gln genotype
 
leptin receptor gene polymorphism GLN223ARG
 
obese women
 
OSAS patients
 
persons carring homozygotic Gln/Gln genotype
 
restriction enzyme analysis
 
single transmembrane protein
 
strong genetic basis
 
superfamily
 
total cholesterol