Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:2.4.2.8 (hypoxanthine-guanine phosphoribosyltransferase)
 2,527 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In the context of the third UKEMS collaborative trial on cell mutation assays, three chemicals have been tested for mutagenicity using the Chinese hamster ovary (CHO) cell/HPRT assay. The protocol employed was based on the re-spreading of monolayer cultures, maintaining one million cells in growth for an expression time of 7 days. Ethyl methanesulphonate gave clear and consistent positive results in the absence of S9 and a clear response to benzo[a]pyrene was obtained with 1% S9. Benzidine gave no evidence of mutagenicity either with or without S9. The results show that the CHO/HPRT assay protocol used in this study is adequate for the detection of potent mutagens. The failure to detect benzidine as a mutagen may be due either to a basic unresponsiveness of the system or to a lack of sensitivity because of the limitation on the numbers of cells which can be maintained during expression. Statistical analysis showed that significant variation occurred between cell survival and mutagenicity estimates for replicate cultures, demonstrating the need for duplicate cultures.
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PMID:Chinese hamster ovary (CHO/HPRT) cell mutation assays with EMS, benzo[a]pyrene and benzidine. 218 15

We utilize T-cell HPRT mutations to monitor exposure to environmental mutagens in siblings of children who have developed cancer at a persistently high rate in Toms River, New Jersey, U.S.A. A preliminary epidemiological study has found a statistically-significant association between drinking public water (by pregnant mother or infant) and subsequent risk for childhood cancer. Three potential sources of mutagenic exposures in Toms River may have increased the rate of carcinogenic initiation significantly in children: 1. Benzidine-based, other azo dye and anthraquinone dye wastes released by Ciba-Geigy, 2. Styrene-acrylonitrile (SAN) trimer and other plastic wastes of Union Carbide, and 3. Radium-224, present in unusually high concentrations in the Cohansey aquifer. Specific patterns of HPRT mutations are utilized to distinguish these various potential sources of carcinogenic exposures in the drinking water of families with childhood cancer and to differentiate chemically or radiologically induced cancers from those which occur spontaneously.
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PMID:Distinguishing potential sources of genotoxic exposure via HPRT mutations. 1113 Sep 45