molecular stutter, a gene defect in which the three-nucleotide code for an amino acid is repeated, missing, or jumbled, causing the gene either to fail to make a specific protein or to make a protein that does not function properly. In Huntington’s disease, for example, the code for glutamine may be repeated 40 or 50 times in a row in the defective gene. The symptoms of Huntington’s disease develop in patients with more than 30 glutamine repeats, and the longer the string of repeats, the earlier the symptoms develop.
