Polymorphisms in Turkish population

Department of Periodontology, School of Dentistry, Ege University, Izmir, Turkey.

Aims: The aims of this study were to investigate (1) the matrix metalloproteinase-1 (MMP-1) promoter polymorphisms in severe chronic periodontitis (CP), (2) the relationship of periodontal therapy outcome with these genotypes, and (3) the gingival crevicular fluid (GCF) MMP-1 levels-MMP-1 genotype correlation. Material and Methods: Genomic DNA was obtained from the peripheral blood of 102 patients with severe CP and 98 periodontally healthy subjects. MMP-1 -519A/G and -1607 1G/2G polymorphisms were determined by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Fifty-eight CP patients received non-surgical periodontal therapy and were followed for 6 months. Clinical periodontal parameters and GCF samples were collected at baseline and at 6 months. GCF MMP-1 levels were analysed by enzyme-linked immunosorbent assay (ELISA). Results: The distribution of MMP-1 genotypes did not significantly differ between the study groups. On the other hand, the -1607 2G allele frequency of severe CP patients was higher than that of healthy subjects. MMP-1 -519G allele carriers had higher GCF MMP-1 levels and percentage of sites with 4-6 mm clinical attachment level (CAL) compared with AA genotypes after non-surgical periodontal therapy (p<0.05). Conclusions: These data suggest that the -1607 2G polymorphic allele of the MMP-1 gene could be associated with susceptibility to severe CP in the Turkish population. It seems that -519AG and GG genotypes could play a role in the outcome of periodontal therapy.

Department of Molecular Medicine, Institute of Experimental Medical Research, University of Istanbul, Istanbul, Turkey.

We investigated the effect of PON 55 and PON 192 polymorphisms on serum PON1 activity and lipid profiles in 213 non-insulin dependent diabetes mellitus (NIDDM) individuals and 116 non-diabetic controls among Turkish subjects. The distribution of PON 55/192 gene polymorphism was determined by polymerase chain reaction-based restriction fragment length polymorphism. Serum lipid levels were measured enzymically. PON activity was measured by spectrophotometric assay of p-nitrophenol production following addition of paraoxon. We found that PON 55 and 192 genotype distribution was similar in patients and controls and paraoxonase activity was generally lower in diabetics than in control subjects. We showed that PON 55 and 192 genotypes have a major effect on serum PON activity. PON 192 BB homozygotes had significantly higher PON activity than AA and AB genotypes among the control and NIDDM populations (p<0.001). PON 55 MM homozygotes had significantly lower PON activity than did LL and LM genotypes in control and NIDDM populations (p<0.05). The PON1 55 and 192 polymorphisms did not consistently influence the serum lipid profiles in either population. In conclusion, our results suggest that the paraoxonase activities are affected by PON1 genetic variability in Turkish NIDDM patients and controls. Copyright 2004 John Wiley & Sons, Ltd.

University of Istanbul, Institute for Experimental Medical Research, Department of Molecular Medicine, Istanbul, Turkey.

Paraoxonase (PON1) is a serum enzyme with an antioxidant function, protecting the low density lipoproteins (LDL) from oxidative modifications. Because diabetic patients are at greater risk of oxidative stress, we investigated the effect of PON1 55 methione (M)/leucine (L) and PON1 192 glutamine (A)/arginine (B) polymorphisms on oxidant-antioxidant system in 213 individuals with type 2 diabetes mellitus and 116 non-diabetic control subjects from Turkish population were included in the study. Polymerase chain reaction (PCR), restriction fragment length polymorphism (RFLP), and agarose gel electrophoresis techniques were used to determine the PON1 genotypes. Thiobarbituric acid reactive substances (TBARS), conjugated dienes levels in the serum and glutathione (GSH) levels in whole blood were measured spectrophotometrically. In both groups PON1 192 AA and PON1 55 MM genotypes had higher TBARS, conjugated dienes levels and lower GSH levels, whereas PON1 192 BB and PON1 55 LL genotypes had lower TBARS, conjugated diene levels and higher GSH level than other genotypes. We thus conclude that PON1 192 BB and PON1 55 LL alleles have protective effect against oxidative stress.

Comment in:

Anadolu Kardiyol Derg. 2005 Sep;5(3):187-8.

Department of Genetics, Institute for Experimental Medical Research, Istanbul Medical School, Istanbul University, Istanbul, Turkey.

OBJECTIVE: The glycoprotein Ia/IIa complex is a major platelet collagen receptor. Its surface expression is influenced by two linked single nucleotide polymorphisms (C807T and G873A) in the glycoprotein Ia (GPIa) gene. In this study we aimed to determine the frequency of GPIa C807T/G873A genotype in patients with myocardial infarction (MI) and healthy controls in Turkish population and association between these dimorphisms and risk factors of MI. METHODS: We examined GPIa (C807T/G873A) genotypes in 158 patients with MI and 145 healthy controls. Distributions of the C807T and G873A dimorphisms were investigated by genotyping DNA using multiplexed allele-specific PCR. RESULTS: There was no association between GPIa genotypes and MI. We further analysed each group for all known risk factors such as plasma lipid levels, cigarette smoking, diabetes, hypertension, gender, age, MI history and body mass index. When compared with other two genotypes for glycoprotein Ia (GT/GA and CC/GG), TT/AA showed an association with higher high-density lipoprotein (HDL) -cholesterol levels in the healthy control group, but none in the group with MI. CONCLUSION: The 807TT/873AA genotype of the GPIa gene alone or in combination with risk factors had no major effect on MI, however, it appears to be associated with higher HDL-cholesterol levels in healthy subjects.