Which of the Following is the Most Common Modification of Nucleic

Question

Which of the following is the most common modification of nucleic acid bases?
A) addition of a methyl group
B) addition of a carboxylic acid
C) addition of a fluorine
D) reduction of a carbonyl to an alcohol

Accepted Answer

The most common modification of nucleic acid bases is the addition of a methyl group, which can occur on either the nitrogen or carbon atoms of the base. This modification is important for regulating gene expression and can be involved in various cellular processes such as DNA repair and replication. The other options listed (addition of a carboxylic acid, addition of a fluorine, reduction of a carbonyl to an alcohol) are much less common modifications of nucleic acid bases.