mutation for deleting certain memory?

is there exist something like that?a mutation in the somatic cells that alter the bases and produce malignant in the brain that enable it to delete certain memory of ours?amnesia causes a person to suffer lost of pre-existed memories and having just memories after the onset of amnesia. in this case, they cannot select which memories they favour, they lost all of them. is there a mechanism where we can actually decide which memories to select and keep. it's just like a memory clean up like we did to our pc. maybe one day, something like that would have happend and i would like to try!end~~