A DNA sequence is shown.

CTG - GAG - CAT

Which sequences show the result of an insertion mutation in the DNA? Check all that apply.

CTG - GGC - AT

CTG - TAT - CAT

TTG - GAG - CAT

CTA - GGA - GCA - T

CTG - GAG - TCG - AT

The last one and the second to last one are insertion.

The right answer is the two statements.

CTA - GGA - GCA - T (adenine insertion)

CTG - GAG - TCG - AT. (thymine and guanine insertion)

A mutation may concern only a single nucleotide of the DNA, either by substitution (A instead of G for example), or by addition (insertion) or loss (deletion). A mutation may involve a chromosome fragment (chromosomal mutation).

Mutation by addition (or insertion) : Insertion of an additional nucleotide Ex: B thalassemia 5 (adenine insertion).