trinucleotide repeat disease

trinucleotide repeat disease

DNA triplet disease, triplet disease Molecular medicine A class of clinically heterogenous diseases, defined by the presence of an abnormal unstable expansion of DNA–triplet repeats in the mutant gene, with up to 200 copies of the repeated trinucleotide Examples Hereditary–CAG repeats–Huntington's disease, Kennedy's disease, CGG–fragile X syndrome, GCT–myotonic dystrophy, spinal and bulbar muscle atrophy; acquired–some forms of colorectal CA. See Fragile X syndrome, Friedreich's ataxia, Huntington's disease, Machado-Joseph syndrome, X-linked spinal and bulbar muscular atrophy.