What is a common breakdown product between amp and gmp degradation to uric acid?

The correct answer is "Xanthine".

Explanation:

Xanthine are molecules that participate as a product on the pathway of degradation of AMP and GMP to uric acid. Xanthine are purine based and are found in most human body fluids. Xanthine oxidase (XO) is the enzyme that catalyzes both degradation pathways, and trough a series of reactions AMP and GMP are degraded into hypoxanthine or xanthine.