Question

Hydroxylamine $\left({\text{NH}}_{\text{2}}\text{OH}\right)$converts cytosine to the compound

shown below.

With which base does this modified cytosine pair? Does this generate a

transition or a transversion mutation?

Short answer

Hydroxylamine$\left({\text{NH}}_{\text{2}}\text{OH}\right)$ converts cytosine to hydroxylaminocytosine. The hydroxylaminocytosine pairs with the adenine base.

Yes, the pairing of hydroxylaminocytosine with adenine leads to transition mutation

Step-by-step solution

Reaction between hydroxylamine and cytosine

Hydroxylamine is a potent mutagen and causes hydroxylation of bases of DNA and gives rise to hydroxylaminocytosine. The hydroxylamine adds OH group to the cytosine. This addition leads to physical changes in cytosine and pairs with adenine.

Transition or a transversion mutation

There are two types of DNA substitution mutations exist. Transition mutation include bases of similar structure because they are interchanges of two-ring purines (A to G) or one-ring pyrimidines (C to T). Transversions entail the exchange of one-ring and two-ring structures because they involve the substitution of pyrimidine bases for purine bases. Therefore the pairing of hydroxylaminocytosine with adenine leads to transition mutation.