Diseases such as Huntington's caused by unstable expansion of three-base repeats.
Repeat sequences expand during replication or meiosis. Huntington's involves CAG repeats coding polyglutamine (36+ repeats cause disease); fragile X involves CGG repeats silencing FMR1. Anticipation means that disease appears earlier and more severely in successive generations as repeats expand.
Diseases such as Huntington's caused by unstable expansion of three-base repeats.
Trinucleotide Repeat Disorders is one of the 54 topics in Genetics. It is rated Advanced, so it suits learners who want specialist depth. Related topics in this area include Frameshift Mutation, Inherited Disorders, Genome-Wide Association Studies.
Huntington's disease usually appears at 30 to 50 years of age with more repeats leading to earlier onset.
Work through the Beginner topics in Genetics first, such as Heredity, Gene, Allele, then return to Trinucleotide Repeat Disorders. Advanced topics assume the Intermediate vocabulary.
The closest topics to Trinucleotide Repeat Disorders are Frameshift Mutation, Inherited Disorders, Genome-Wide Association Studies, Chromosomal Mutations. Comparing them side by side is a good way to see how the ideas connect.
Read the summary and the in-depth section, then use the quick check on the interactive lesson for Trinucleotide Repeat Disorders. To practise the whole of Genetics, use the Genetics quiz.
Trinucleotide Repeat Disorders: Diseases such as Huntington's caused by unstable expansion of three-base repeats. Frameshift Mutation: Insertion or deletion of nucleotides not in multiples of three that shifts the reading frame of the codons. Read both side by side and note what each one explains.
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with Frameshift Mutation and explain the difference aloud. Finally, take the Genetics quiz and come back to this page for any question you miss.
Insertion or deletion of nucleotides not in multiples of three that shifts the reading frame of the codons.
🧬 GeneticsConditions caused by faulty genes passed through families, such as cystic fibrosis and sickle cell disease.
🧬 GeneticsScan many genomes for variants statistically linked to a trait or disease.
🧬 GeneticsLarge structural changes including deletions, duplications, inversions and translocations of chromosome segments.
🧬 Genetics