MinervaBMJ 1995; 310 doi: https://doi.org/10.1136/bmj.310.6972.138 (Published 14 January 1995) Cite this as: BMJ 1995;310:138
Cells have built in mechanisms for repair of mismatches in the pairing of the purine bases in DNA, and defects in this repair system are thought to be an important factor in many cancers (Science 1994;266:1959–60). Hereditary non-polyposis colorectal cancer, for example, is due to an autosomal dominant defect in which one of a pair of repair genes is faulty. Tumour cells in patients with this type of cancer are defective in both copies of the gene. Failure of the repair process is thought to allow the survival of mutations that circumvent the controls on cell proliferation.
A comparison reported in “Gut” (1995;36:87–9) of two tests for intestinal bleeding, the guaiac occult blood test and the faecal (alpha)1-antitrypsin test, concluded that neither was sufficiently sensitive to be recommended for routine use in screening asymptomaticpatients for possible bowel cancer. For patients at high risk the best bet seems to be colonoscopic screening at intervals of around four years.
Hypoglycaemia may occasionally induce angina: a case report from the United States (Annals of Internal Medicine 1994;121:945–6) describes a woman aged 61 in whom angina was the only symptom of hypoglycaemia. After a bypass graft she lost her angina and developed …