Polymorphisms in Turkish population

Turk Kardiyol Dern Ars. 2009 Oct;37(7):473-8.

Taşkiran P, Cam SF, Sekuri C, Tüzün N, Alioğlu E, Altintaş N, Berdeli A.

Department of Medical Biology and Genetics, Medicine Faculty of Celal Bayar University, Manisa, Turkey.

OBJECTIVES: Paraoxonase (PON1) is a high-density lipoprotein (HDL)-associated esterase that hydrolyses lipoperoxides. PON1 serves as a protective factor against oxidative modification of LDL, suggesting that it may play an important role in the prevention of atherosclerotic process. Research has focused on two polymorphisms: leucine (L allele) to methionine (M allele) substitution at codon 55, and glutamine (A allele) to arginine (B allele) substitution at codon 192. STUDY DESIGN: We examined amino acid changes at codon 55 and 192 in the PON1 gene by polymerase chain reaction and using restriction enzymes in 120 patients (92 men, 28 women; mean age 48.2+/-4.3 years) with premature coronary artery disease (CAD) and in 102 healthy subjects (80 men, 22 women; mean age 46.8+/-5.2 years) with no history of CAD and a normal electrocardiogram. RESULTS: Distribution of genotypes in the patient and control groups at codon 55 were 6.7% and 4.9% for MM, 46.7% and 29.4% for LM, 46.7% and 65.7% for LL, respectively. The frequency of genotypes at codon 192 were as follows: 4.2% and 2% for RR, 40% and 35.3% for QR, and 55.8% and 62.8% for QQ, respectively. While the frequency of PON1 55M allele was higher in the CAD group (0.3 vs. 0.2), PON1 192R allele frequency did not differ (p>0.05). There was a significant relationship between the PON1 M/L55 polymorphism and CAD (p=0.017), whereas the R/Q192 polymorphism was not associated with CAD (p=0.445). CONCLUSION: These data suggest that the PON1 M/L55 polymorphism shows a significant relationship with CAD and the Q/R192 polymorphism is not a major risk factor causing susceptibility to CAD in our population.

Author(s): Demirdogen BC (Demirdogen, Birsen Can)1, Demirkaya S (Demirkaya, Seref)2, Turkanoglu A (Turkanoglu, Aysun)1, Bek S (Bek, Semai)2, Arinc E (Arinc, Emel)1, Adali O (Adali, Orhan)1
Source: CELL BIOCHEMISTRY AND FUNCTION Volume: 27 Issue: 8 Pages: 558-567 Published: DEC 2009

Abstract: Background Paraoxonase 1 (PON1) is protective against the development of atherosclerosis. a risk factor for ischemic stroke. PON1 gene has one promoter region (-107T/C) and two coding region (192Q/R and 55L/M) polymorphisms that affect the levels and catalytic efficiency of the enzyme. respectively. In this study. we aimed to determine the importance of -107T/C. 192Q/R and 55L/M polymorphisms of PON1 gene and three PON1 activity (diazoxonase, paraoxonase, arylesterase) as risk factors for ischemic stroke
Methods Stud population was comprised of 172 unrelated adult Caucasian patients with acute hemispheric ischemic stroke and 105 symptom-free controls. Genotypes were attained by PCR followed by restriction enzyme digestion and phenotypes were determined by spectrophotometric assays.

Results This is the first study analyzing diazoxonase activity as a risk factor for ischemic stroke Nevertheless, diazoxonase, paraoxonase and arylesterase activities were almost the manic in stroke patients and controls The 107TT genotype was associated with a 1 97 times increased risk for stroke in elderly (age > 59). Individuals with this genotype were found to have the lowest PON1 enzyme activities among the -107T/C genotypes Triple combined haplotype QRLMTC was found to be 6.94- and 10.4-times protective against ischemic stroke in the overall and the elderly Population. respectively. 55LL genotype was associated with 1 78-fold increase in the risk of ischemic stroke

Conclusion PON1 genotypes, but not activities, are related with the risk of stroke. Copyright (C) 2009 John Wiley & Sons, Ltd

Document Type: Article
Language: English
Author Keywords: genotype; paraoxonase; PON1; polymorphism; stroke
KeyWords Plus: HUMAN-SERUM PARAOXONASE; LOW-DENSITY-LIPOPROTEIN; INTIMA-MEDIA THICKNESS; LIPID-PEROXIDATION; LDL OXIDATION; ARYLESTERASE; PROMOTER; PROTEIN; ATHEROSCLEROSIS; CHOLESTEROL
Reprint Address: Demirdogen, BC (reprint author), Refik Saydam Natl Publ Hlth Agcy, Directorate Food Safety & Nutr Res, Ankara, Turkey
Addresses:
1. Middle E Tech Univ, Dept Biochem, Inst Nat & Appl Sci, TR-06531 Ankara, Turkey
2. Gulhane Mil Med Acad, Dept Neurol, Ankara, Turkey

Folia Biol (Praha). 2009;55(2):35-40

Isbilen E, Yilmaz H, Arzu Ergen H, Unlucerci Y, Isbir T, Gurdol F.

Department of Biochemistry, Faculty of Medicine, Baskent University, Ankara, Turkey.

Paraoxonase 1 (PON1) is thought to influence serum homocysteine concentrations, at least in part, due to its homocysteine thiolactonase activity and to play a role in preeclampsia and atherosclerosis. We investigated the effects of PON 55 and PON 192 polymorphisms on plasma total homocysteine (tHcy) concentrations in preeclamptic and healthy pregnants among Turkish population (N = 106). PON 55 and 192 genotypes were determined by PCR RFLP techniques. Plasma tHcy concentrations were measured by high-performance liquid chromatography. No differences were observed in the distribution of PON 1 55/192 genotypes and allele frequencies between the preeclamptic and healthy pregnants. tHcy level in the plasma of preeclamptic women was found to be increased in comparison with healthy pregnants (P < 0.01). Preeclamptic women bearing the mutated PON 192 RR and wild-type PON1 55 LL genotypes had higher tHcy levels than those of the healthy pregnants with the corresponding genotypes, supporting the possibility that the hyperhomocysteinaemia seen in preeclamptic women is associated with the PON genotypes. However, no influence of the allelic distribution on plasma tHcy concentrations was detected in either group. Our results suggest that PON1 55 and 192 genotypes might have an important role in developing hyperhomocysteinaemia and may also have a role in the pathogenesis of preeclampsia in a Turkish population.