Insertion or deletion of nucleotides not in multiples of three that shifts the reading frame of the codons.
Adding or removing one or two bases shifts the codon grouping and changes every downstream amino acid, usually leading to an early stop codon and a nonfunctional protein. Insertions or deletions in multiples of three preserve the frame but add or remove amino acids.
Frameshifts are generally more damaging than substitutions.
Insertion or deletion of nucleotides not in multiples of three that shifts the reading frame of the codons.
Frameshift Mutation is one of the 54 topics in Genetics. It is rated Intermediate, so it suits learners who already know the core vocabulary. Related topics in this area include Point Mutations, Trinucleotide Repeat Disorders, Chromosomal Mutations.
Tay-Sachs disease is often caused by a 4-base insertion in the HEXA gene.
Work through the Beginner topics in Genetics first, such as Heredity, Gene, Allele, then return to Frameshift Mutation. Intermediate topics assume the Beginner vocabulary.
The closest topics to Frameshift Mutation are Point Mutations, Trinucleotide Repeat Disorders, Chromosomal Mutations, 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 Frameshift Mutation. To practise the whole of Genetics, use the Genetics quiz.
Frameshift Mutation: Insertion or deletion of nucleotides not in multiples of three that shifts the reading frame of the codons. Point Mutations: Changes to a single nucleotide, classed as silent, missense or nonsense depending on the effect on the protein. 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 Point Mutations and explain the difference aloud. Finally, take the Genetics quiz and come back to this page for any question you miss.
Changes to a single nucleotide, classed as silent, missense or nonsense depending on the effect on the protein.
🧬 GeneticsDiseases such as Huntington's caused by unstable expansion of three-base repeats.
🧬 GeneticsLarge structural changes including deletions, duplications, inversions and translocations of chromosome segments.
🧬 GeneticsPermanent changes in the DNA sequence that can be harmless, harmful or occasionally beneficial.
🧬 Genetics