You got this all wrong people!
The commas are stating the age of the Sharingan user!
At first the little child doesnt have any Sharingan, then he has two commas, after growing up and becoming adult he gets three commas..
just ONE nanosecond before he dies he gets the fourth comma

AND THEN, who ever eats the bastard's body gets a brand new Sharingan eyes with five commas around the pupil, but he gets poisoned, he dies and the eyes burn.

(where the hell did I make that up from?)