[The peculiarities of polymorphism of XPD and XRCC1 repair genes in cells of Down and Ehlers-Danlo syndrome patients characterized by increased radiosensitivity].

Codon 312 and 751 polymorphisms ofXPD gene and codon 399 polymorphism of XRCC1 gene of peripheral blood lymphocytes in patients with Down syndrome (DS) (46 individuals), Ehlers-Danlo syndrome (EDS) (47 individuals) and in a group of healthy donors (control) (40 individuals) have been studied. Frequency of XPD genotype (G312G) coding for the most effectively functioning form of XPD protein was lower in patients with DS (26%) than in a group of healthy donors (42.5%) (p = 0.

[Investigation of detoxification polymorphisms genes, methylenetetrahydrofolate-reductase (MTHFR) and P53 in the radiosensitive human cells].

The genes of detoxication, MTHFR and p53 were studied in Down' and Ehlers-Danlos syndrome cells. The frequency GSTM1(0/0) genotype in Down syndrome patients was in 1.5 times higher than in control cells (p < 0.

[Antimutagenes' protection action in human repair-defected cells].

The action of natural (garlick extract, retinol) and of synthetic (crown-compound) antimutagenes in lymphotytes with gamma-radiation-induced inhibition of DNA-damages repair in cases of Elers-Danlos, syndrom, progeria and gomocystinurea was studied. Antimutagen cells defence from mutagenes was shown at all cases except one: progeria cells treated by retinol. Thus the repair-deficient cells resistance against mutagenes could be increased by antimutagenes.

[Genetic polymorphism of glutathione-S-transferases and inhibition of DNA repair].

A complex investigation of different cell defence systems, such as: DNA repair, antioxidant system (SOD), xenobiotic detoxification system (glutathione-S-transferases M1 and T1), radioadaptive response (RAR) in lymphocytes of patients with hereditary disease of connective tissue (Elers-Danlose syndrome) was carried out. The frequency of genotype GSTM1 (0/0) in children with Elers-Danlose syndrome (23%) is lower as compared to the control group (44%). The lymphocytes of children with Elers-Danlose syndrome were characterized by reduced ability to repair gamma-induced damage of DNA.

[DNA repair and antioxidant defence in the repair-deficient human cells (Marfan's syndrome) after gamma-irradiation].

DNA repair synthesis (RS) was investigated in lymphocytes of healty donors and repair-deficient cells (Marfan's syndrome), treated with inhibitor of superoxidedismutase (SOD)--TRIEN--after gamma-irradiation. Significant difference was revealed in cells of healthy donors and Marfan's syndrome: in cells of healthy donors TRIEN stimulated DNA RS whereas this effect didn't observed in Marfan's syndrome cells. So it is possible to suppose that SOD activity is different in normal and gamma-repair-deficient cells.