Journal of Sleep Disorders & Therapy
Open Access

Abstract

Frequency of Human Leukocyte Antigens, Plasminogen Activator Inhibitor-1 and Methylenetetrahydrofolate Reductase Gene Polymorphisms in Obstructive Sleep Apnea-Hypopnea Syndrome with or without Pulmonary Artery Hypertension

Domenico Maurizio Toraldo, Francesco De Nuccio, Salvatore Mauro, Francesco Spirito, Alessandro Distante and Giuseppe Nicolardi

Background: The aim of this study was to investigate relationships between the genotypic frequencies of genes F5-coagulation factor V (proaccelerin, labile factor), F2-coagulation factor II (thrombin), MTHFRmethylenetetrahydrofolate reductase (NADPH), PAI-1 - plasminogen activator inhibitor-1, the frequencies of HLA haplotypes DQ2/DR3, DQ2/DR7, DQ8/DR4, 5, DQ7/DR5 and clinical features and severity of OSAS in comparison to a control population of 163 patients without OSAS.
Methods and results: Eighty-two consecutive outpatients with OSAS were enrolled in the respiratory, cardio, and genetic study. By means of cluster analysis it was shown that 40% of patients with PAI-1 5G/5G polymorphism had pulmonary artery hypertension, with a mean value of 46 mm Hg, and also 40% of OSAS patients with pulmonary artery hypertension had PAI-1 5G/5G polymorphism, 50% had 4G/5G and 10% had 4G/4G; as regards OSAS patients without PH, 8.95% only had PAI-1 5G/5G polymorphism, 22.38% had PAI-1 4G/4G and 67.16% had PAI- 1 4G/5G. PAI-1 polimorphisms were detected by RDB techniques. Moreover, these patients with OSAS showed HLA haplotypes polymorphism: DQ7 (40%), DQ2.5 (20%) and DQ2.2 (10%). Nevertheless, OSAS patients without PAH showed HLA polymorphism as follows: DQ7 (47, 76%); DQ2.5 (8.95%); DQ2.2 (16.41%). OSAS patients with pulmonary hypertension were 12.99 % of all OSAS patients. HLA polymorphism was analyzed by PCR amplification and gel electrophoresis.
Conclusions: Our results suggested a genotypic heterogeneity among OSAS patients PAI-1 5G/5G polymorphism with PAH possibly in relation with severity of the disease.