7-Methylguanosine (m7G) is a modified purinenucleoside. It is a methylated version of guanosine and when found in human urine, it may be a biomarker of some types of cancer. In the RNAs, 7-methylguanosine have been used to study and examine the reaction evolving methylguanosine. It also plays a role in mRNA as a blocking group at its 5´-end.[1]
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