Metabolic errors can spell doom for DNA
Many critical cell functions depend on a class of molecules called purines, which form half of the building blocks of DNA and RNA, and are a major component of the chemicals that store a cell’s energy. Cells keep tight control over their purine supply, and any disruption of that pool can have serious consequences.In a new study, MIT biological engineers have precisely measured the effects of errors in systems for purine production and breakdown. They found that defects in enzymes that control these processes can severely alter a cell’s DNA sequences, which may explain why people who carry certain genetic variants of purine metabolic enzymes have a higher risk for some types of cancer.DNA usually consists of a sequence of four building blocks, or nucleotides: adenine, guanine, cytosine and thymine (the A, G, C and T “letters” that make up the genetic code). Guanine and adenine are purines, and each...