Mutations

What is a point mutation?

What is a point mutation?

Involves a chemical change in just one base pair and can be enough to cause a genetic disorder

Substitution

A point mutation in which one base is exchanged for antoher

Missense muations

the DNA code is altered so that it codes for the wrong amino acid

Nonsense mutation

change the codon for an amino acid to a stop codon

What do nonsense mutations lead to?

Proteins that cannot function properly

Insertions

additions of nucleotide to the DNA sequence

What does insertions and deletion change?

the multiples of three bases from the point of the insertion or deletion

Frame shift mutations

insertion and deletion

switches the frame of the amino acid sequence

Tandem repeats

involves an increase in the number of copies of repeated codons

How do point mutations occur?

spotaneously

Causes of mutation from DNA polymerase

During replication, DNA polymerase adds the wrong nucleotides