Harry - as Sheehan would say, do some searching on the forum. This has been discussed before. Hahahahahaha.
Yes, very normal to have tye green motyling on the skin. Doesnt have to have it but very charcteristic of the 27-1. Birthmark, eh, dont know if that is the correct term or not but i have heard this mentiined in discussions of various mangoes having such mark from Walter, so it would make sense that Marlys (the woman John describes above) would say this also.