Basal and induced micronucleus frequencies in human lymphocytes with different GST and NAT2 genetic backgrounds.
Basal and induced frequencies of genetic damage can be modulated by different host factors, including genes involved in phase II metabolism. Since polymorphic variants in the glutathione S-transferase (GST) and N-acetyl transferase (NAT) genes have been associated with cancer risk, we explored the possible links between GSTM1, GSTP1, GSTT1 and NAT2 variants and the frequency of micronuclei (MN) in human lymphocytes. This exploratory study was carried out in 30 thyroid cancer patients, before and after receiving an average dose of 109.9+/-1.3 mCi radioactive iodine as a co-adjuvant therapy. The results indicate that none of the polymorphisms studied show any kind of association with the basal level of micronuclei. When the same patients were followed after radioiodine exposure, a significant increase in the frequency of MN was observed in practically all of them (28/30), indicating the genotoxic activity of the ionising radiation exposure. The increase in MN frequency was not associated with any of the GST polymorphisms evaluated. Nevertheless, the presence of slow acetylator phenotypes and, in particular, the presence of the NAT2*7 allele was significantly associated with a lower increase of the MN frequency after radioiodine treatment.
Hernández
Alba
A
Grup de Mutagènesi, Departament de Genètica i de Microbiologia, Universitat Autònoma de Barcelona, Bellaterra, Spain.
Xamena
Noel
N
Gutiérrez
Sara
S
Velázquez
Antonia
A
Creus
Amadeu
A
Surrallés
Jordi
J
Galofré
Pere
P
Marcos
Ricardo
R
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000483:Alleles; D001191:Arylamine N-Acetyltransferase / Q000235:genetics*; D002648:Child; D005260:Female; D005838:Genotype; D005982:Glutathione Transferase / Q000235:genetics*; D006801:Humans; D008214:Lymphocytes / Q000201:enzymology* / Q000378:metabolism / Q000473:pathology*; D008297:Male; D048629:Micronuclei, Chromosome-Defective; D015162:Micronucleus Tests; D008875:Middle Aged; D011110:Polymorphism, Genetic; D013964:Thyroid Neoplasms / Q000235:genetics
D001191:Arylamine N-Acetyltransferase; C478900:NAT2 protein, human; D005982:Glutathione Transferase