Genetically significant dose

Genetically significant dose (GSD) A radiation dose that, if received by every member of the population, would produce the same total genetic injury to the population as the actual doses received by the various individuals. 

Nuclear power plant to critical group (Sweden) X-ray investigation barium meal (intestine) intravenous urography abdomen and lung mean gonadal dose (abdomen), genetically significant dose dental... 

Mercaptopurine (6-MP) is an oral purine analog that is converted to a ribonucleotide to inhibit purine synthesis. Mercaptopurine is converted into thiopurine nucleotides, which are catabolized by thiopurine S-methyltransferase (TPMT), which is subject to genetic polymorphisms and may cause severe myelosuppression. TPMT status may be assessed prior to therapy to reduce drug-induced morbidity and the costs of hospitalizations for neutropenic events. Mercaptopurine is poorly absorbed, with a time to peak concentration of 1 to 2 hours after an oral dose. The half-life is 21 minutes in pediatric patients and 47 minutes in adults. Mercaptopurine is used in the treatment of acute lymphocytic leukemia and chronic myelogenous leukemia. Significant side effects include myelosuppression, mild nausea, skin rash, and cholestasis. When allopurinol is used in combination with 6-MP, the dose of 6-MP must be reduced by 66% to 75% of the usual dose because allopurinol blocks the metabolism of 6-MP. 

The effect of a standard dose of succinylcholine lasts only about 10 min. It is often given at the start of anesthesia to facilitate intubation of the patient. As expected, choUnesterase inhibitors are unable to counteract the effect of succinylcholine. In the few patients with a genetic deficiency in pseudocholinesterase (= nonspecific cholinesterase), the succinylcholine effect is significantly prolonged. 

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