Lab Tests Online - Explaining Pathology

Glossary

Triplet repeat disorders


Also known as: Trinucleotide repeat disorders; Triplet repeat expansion disorders

These are diseases where a group of three nucleotides in the person’s DNA are repeated an abnormally large number of times. The affected person develops the disease when the number of repeats exceeds a threshold. This threshold number varies for different genes and disorders. Fragile X syndrome and Huntington’s disease are examples of triplet repeat disorders.