Methylnitronitrosoguanidine (MNNG[2] or MNG, NTG when referred to colloquially as nitrosoguanidine[3]) is a biochemical tool used experimentally as a carcinogen and mutagen.[1] It acts by adding alkyl groups to the O6 of guanine and O4 of thymine, which can lead to transition mutations between GC and AT. These changes do not cause a heavy distortion in the double helix of DNA and thus are hard to detect by the DNA mismatch repair system.
One of the earliest uses of methylnitronitrosoguanidine was in 1985. A group of scientists tested whether or not the chemical composition of methylnitronitrosoguanidine would directly affect the growth of tumors and cancer cells in rats.[citation needed]
In the experiment, the cancer cells from a Japanese cancer patient was injected into 8 rats. The biochemical tool and showed a decline of cancer cells in a few of the rats' bodies.
In organic chemistry, MNNG is used as a source of diazomethane when reacted with aqueous potassium hydroxide.[4]
MNNG is a probable human carcinogen listed as an IARC Group 2A carcinogen.[5]
MNNG produces diazomethane (known DNA methylating agent) in basic aqueous solutions, and nitrous acid (also mutagenic) in acidic solutions.[6]