Allele frequencies and forensically relevant population statistics of 22 short tandem repeat (STR) loci were determined from 303 unrelated Estonian individuals. The samples were amplified with three kits: the AmpFlSTR(®) Identifiler, the PowerPlex(®) ESI 16 and the PowerPlex(®) 16. No significant deviation from Hardy-Weinberg equilibrium was detected, except for locus D22S1045. Investigated loci are very discriminating in Estonian population, with a combined discrimination power of 0.9999999999999999999999999877. Furthermore, a comparison with previously published frequency data from other nearby populations is presented.

Primary open-angle glaucoma, the most common form of glaucoma is a slowly progressive atrophy of the optic nerve, characterized by loss of peripheral visual function and is usually associated with elevated intraocular pressure. The etiology and genetic risk factors of primary open-angle glaucoma are mostly unknown. The aim of this study was to find out whether the polymorphism at GSTM1, GSTM3, GSTT1 and GSTP1 loci is associated with increased susceptibility to glaucoma, because these polymorphic enzymes are susceptibility candidates for several diseases, including such eye disease as cataract. The phenotype of GSTM1 and GSTT1 was determined by ELISA and the genotype of GSTM3 and GSTP1 was detected by polymerase chain reaction. Four hundred and fifty two Estonians (250 glaucomas and 202 controls) participated in a case-control study. A significant association of the GSTM1 polymorphism with glaucoma was observed. The frequency of the GSTM1 positive individuals among the glaucoma group was significantly higher than in controls (60 vs. 45.0%) with odds ratio of 1.83 (95% CI 1.26-2.66;P = 0.002). The risk among the GSTM1 positive individuals of developing glaucoma was even higher in the case of smoking: 62.7% of smokers were GSTM1 positive in the glaucoma group while only 33.3% of smokers had GSTM1 positive phenotype in controls (OR = 3.36; 95% CI 1.49-7.56;P = 0.012). An association with a lower level of significance was also found with the GSTM3 gene. Four% of the 250 patients with POAG were identified as carriers of the GSTM3 BB genotype, a proportion which was slightly higher than the 1.0% for the controls (OR = 4.17; 95% CI 0. 90-19.24;P = 0.144). The frequencies of the GSTT1 and GSTP1 genotypes in both groups were not statistically different. The present study suggests that the GSTM1 polymorphism may be associated with increased risk of development of primary open-angle glaucoma.

PURPOSE:To investigate the possible association between glutathione S-transferase GSTM1, GSTM3, GSTT1, and GSTP1 polymorphism and the occurrence of age-related cataracts in Estonian patients.METHODS:Patients with cortical (155), nuclear (77), posterior subcapsular (120), mixed type (151) of senile cataract and control individuals (202) were phenotyped for GSTM1 and GSTT1 by enzyme-linked immunosorbent assay and genotyped for GSTM3 and GSTP1 by polymerase chain reaction.RESULTS:The frequency of the GSTM1-positive phenotype was significantly higher in the cortical cataract group (60.6%) than in the controls (45.0%) with odds ratio of 1.88 (95% CI, 1.23-2.94; P = 0.004). The cortical cataract risk associated with the GSTM1-positive phenotype was increased in carriers of the combined GSTM1-positive/GSTT1-positive phenotype (OR = 1.99; 95% CI, 1.30-3.11; P = 0.002) and the GSTM1-positive/GSTM3 AA genotype (OR = 2.28; 95% CI, 1.51-3.73; P < 0.001). The highest risk of cortical cataract was observed in patients having all three susceptible genotypes (OR = 2.56; 95% CI, 1.59-4.11; P < 0.001). Also, a significant interaction between the presence of the GSTP1* A allele and cortical cataract was found with prevalence of the GSTP1* A allele among the cortical cataract cases compared with the controls. Ninety-five percent of subjects with cortical cataract had the GSTP1 (AA, AB, or AC) genotype, whereas in controls 87% of persons had a genotype with GSTP1*A allele (OR = 3.1; 95% CI, 1.31-7.35; P = 0.007). In contrast to the GSTP1*A allele, the presence of the GSTP1*B allele in one or two copies leads to decreased cortical cataract risk (OR = 0.09 for GSTP1 BB genotype). CONCLUSIONS. The GSTM1-positive phenotype as well as the presence of the GSTP1*A allele may be a genetic risk factor for development of cortical cataract.

The distribution of glutathione S-transferase T1 (GSTT1) phenotypes was studied in a total sample of 673 Estonians whose four grandparents were born in Estonia, by an ELISA test able to differentiate between GSTT1 positive and GSTT1 negative phenotypes. 18% of the total sample did not present GSTT1-1 protein in whole blood. GSTT1-1 concentration was assayed in 519 out of the 552 GSTT1 positive subjects (i.e. 82% of the total sample) 49% percent of this subsample made up by 519 subjects was found to have GSTT1-1 in intermediate concentration and 33% in high concentration. The gene frequency of the GSTT1 deleted allele was estimated to be 0.423 as the square root of the frequency of the GSTT1 negative subjects (square root of 0.18 = 0.423) and that of the GSTT1 positive allele as (1-0.423) = 0.577. Statistically significant regional differences were found within the population with the lowest frequency of GSTT1 negative in western Estonia (9.5%) and the highest in the southeastern part of the country (24.5%).