Gundacker, Wittmann et al. 2009
Gundacker, Wittmann et al. 2009
GUNDACKER, C., K.J. WITTMANN, M. KUKUCKOVA, G. KOMARNICKI, I. HIKKEL & M. GENCIK, 2009. Genetic Background of Lead and Mercury Metabolism in a Group of Medical Students in Austria. Environmental Research, 109 (6): 786-796 + online Supplement A.
Published online 9 June 2009. https://doi.org/10.1016/j.envres.2009.05.003
Background: The heavy metal mercury is a ubiquitous environmental pollutant with high neurotoxic potential. Information on the impact of genetic predisposition on mercury toxicokinetics in the human body is limited. 324 medical students were examined in order to detect potential associations between mercury exposure and common polymorphisms in glutathione-S-transferase (GSTT1, GSTM1, GSTP1, GSTA1), glutamate cysteine ligase (GCLC), and metallothionein (MT1, MT2, MT4) genes. Gene expression of MT1 was evaluated in a further group of students (N=30).
Methods: Mercury exposure of students was determined by blood, urine, and hair analyses (CV-AAS). Genotyping of polymorphisms was examined by MALDI-TOF MS and the TaqMan methodology. Expression of MT1 gene was analyzed in lymphocytes from fresh peripheral blood by semiquantitative RT-PCR. Associations between mercury exposure and genetic background were examined by bivariate analysis, and by categorical regression analysis (CATREG) controlled by metal- and matrix-specific variables.
Results: Mercury levels in urine, blood, and hair indicated low exposures. GSTP1-114 and MT4 gene polymorphisms as well as dual gene combinations including GSTP1, GCLC, GSTT1, and GSTM1 polymorphisms were independent variables related to mercury body burdens (CATREG P0.05). GSTP1-114/GSTT1 and GSTP1-105/GCLC combinations showed synergistic effects on hair mercury levels compared to single gene variants. MT1X expression was higher in persons with the intact GSTT1, GSTM1 genotype.
Conclusions: We found evidence that certain genetic backgrounds were associated with increased mercury retention. This might indicate a reduced ability for detoxification, which would render the human organism susceptible to mercury exposure. The potential relationship between GST-genotype and MT1-gene expression needs further investigation.
heavy metals; mercury; detoxification; susceptibility; genetic background
Homo sapiens