M1dG

FULL NAME: guanine-malondialdehyde adduct


DESCRIPTION:
Pyrimido[1,2-a]-purin-10(3H)-one (M1G) is a secondary DNA damage product arising from primary reactive oxygen species (ROS) damage to membrane lipids or deoxyribose. M1G is a heterocyclic compound which is a by-product of base excision repair (BER) of a specific type of DNA adduct called M1dG. The M1dG adduct in turn is formed by a condensation reaction between guanosine nucleotides in DNA and either malondialdehyde or base propenal. If not repaired (by NER), these adducts are mutagenic and carcinogenic. Malondialdehyde is an end product of lipid peroxidation while base propenal is a result of DNA peroxidation. M1dG is the major endogenous DNA adduct in humans. M1dG adducts have been detected in cell DNA in liver, leucocytes, pancreas and breast in concentrations of 1-120 per 10v8 nucleotides. Detection and quantification of M1dG adducts in the body as measured by free M1G is a tool for detecting DNA damage that may lead to cancer. Free M1G is also biomarker for oxidative stress.

DAMAGE TYPE: DNA adduct


DNA DAMAGE SOURCE(S) (MAIN):
lipid peroxidation (LPO)
reactive oxygen species (ROS)
malondialdehyde (MDA)


DNA DAMAGE EFFECT(S) (MAIN):
carcinogen
G→A transition
G→C transversion
G→T transversion
mutagenesis
point mutation
substitution
transition
transversion


DNA DAMAGE EFFECT(S) (MINOR):
insertion
point mutation


PATHWAYS:
Fanconi anemia (FA) pathway
nucleotide excision repair (NER)
prokaryotic (SOS) response


DNA repair protein(s) related to damage:
UvrC
UvrB
ERCC5 (XPG)
ERCC4 (XPF)


Last modification date: Oct. 12, 2011