Mutations and genetic variants
I can explain how mutations in DNA cause genetic variants.
Mutations and genetic variants
I can explain how mutations in DNA cause genetic variants.
Lesson details
Key learning points
- A change in the sequence of nucleotide bases in the DNA of the genome is called a mutation.
- Mutations can be caused by some substances and by ionising radiation.
- Most mutations are caused by errors when DNA is copied, when cells divide to make new cells.
- How substitution, insertion and deletion mutations change the base sequence in DNA.
- A mutation creates a genetic variant (a region of DNA in which the sequence of nucleotide bases has been changed).
Common misconception
Mixing up amino acids and nucleotides, also nucleotides and bases.
Activity checks: Nucleotides contain a base; DNA is a polymer of nucleotides that codes for the order of amino acids in a protein.
Keywords
DNA - DNA is a large chemical molecule made of smaller chemical groups. It carries the genetic code of all living organisms.
Nucleotide - Nucleotides are the chemical groups that are the building blocks of DNA. The four types are coded A, T, C and G.
Mutation - A mutation is a change in the nucleotide base sequence in the DNA of the genome.
Ionising radiation - Ionising radiation (e.g. X-rays, gamma rays and high-energy ultraviolet) can cause mutations in DNA.
Genetic variant - A genetic variant is produced when a mutation causes a change in the genetic sequence of a gene or a non-coding region of DNA.
Licence
This content is © Oak National Academy Limited (2024), licensed on Open Government Licence version 3.0 except where otherwise stated. See Oak's terms & conditions (Collection 2).
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a change in the nucleotide base sequence in the genome
a substance that can cause changes to DNA
a type of ionising radiation that can cause changes to DNA
a chain of nucleotides joined together