title: Identification of NQO1 and GSTs genotype frequencies in Bulgarian patients with Balkan endemic nephropathy.
abstract: BACKGROUND
  Polymorphisms in NAD[P]H:quinone oxidoreductase (NQO1) and glutathione S-transferases (GSTs) have been reported to be associated with an increased risk for environmentally and/or occupationally induced renal and bladder cancers. Genetic factors related to chronic nephropathy and to urinary bladder or renal cancer development in Balkan endemic nephropathy (BEN) is unknown. In order to evaluate their possible role in BEN susceptibility, we determined the frequencies of NQO1 alleles *1, *2 and *3, as well as the GSTT1 and GSTM1 null genotypes in BEN patients and healthy subjects from a non-endemic region of Bulgaria.
  
  
  METHODS
  The respective genotypes of 95 unrelated Bulgarian BEN patients and of 112 healthy individuals (control group) were determined by rapid cycle polymerase chain reaction (PCR) and detected with either SYBR green I fluorescent dye or melting curve analysis using allele specific probes.
  
  
  RESULTS
  NQO1 genotyping showed a higher NQO1*2 allele frequency (23.68%) in BEN patients compared to controls (18.75%; p=0.219), while NQO1*3 allele frequencies were similar in both groups (2.63% in BEN patients vs. 2.23% in controls; p=0.791). The GSTT1 deficiencywas observed in 20% of BEN patients vs. 16.1% of controls (p=0.613). The GSTM1 null genotype was found in 45.3% of BEN patients vs. 51.8% of controls (p=0.674). There was no influence of NQO1 and GSTs genotypes found on BEN risk.
  
  
  CONCLUSIONS
  Our results established that alleles NQO1*2 and NQO1*3, as well as lack of GSTT1 and GSTM1 did not influence the BEN risk. These findings provide novel information on the genetic heterogeneity in the healthy Bulgarian population.
authors.affiliation: Department of Medical Genetics, Medical University, Sofia, Bulgaria. dragatoncheva@yahoo.net
authors.forename: Draga I
authors.initials: DI
authors.lastname: Toncheva
authors.forename: Nicolas
authors.initials: N
authors.lastname: Von Ahsen
authors.forename: Srebrena Y
authors.initials: SY
authors.lastname: Atanasova
authors.forename: Tzvetan G
authors.initials: TG
authors.lastname: Dimitrov
authors.forename: Victor W
authors.initials: VW
authors.lastname: Armstrong
authors.forename: Michael
authors.initials: M
authors.lastname: Oellerich
mesh_terms: D001449:Balkan Nephropathy / Q000235:genetics*; D002031:Bulgaria; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D005838:Genotype; D005982:Glutathione Transferase / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D016660:NAD(P)H Dehydrogenase (Quinone) / Q000235:genetics*; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic
chemical_list: D005982:Glutathione Transferase; D016660:NAD(P)H Dehydrogenase (Quinone); C447479:NQO1 protein, human; C413545:glutathione S-transferase T1