Genetic toxicity base substitutions

The feature of all inherited disorders is a genetic defect, often the result of a single base substitution or deletion in the DNA. which results in the reduced synthesis of a particular protein or in the synthesis of a protein with an altered amino acid coniposiiion. A classical inborn error of metaholisni involves a missing or defective en/yme which causes a block on a metabolic pathway and the production of toxic metabolites. More than four thousand disorders involving single genes have been identified. 

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