“Diarrhea is hereditary. It runs in your jeans”

“Diarrhea is hereditary. It runs in your jeans”—a pun on “genes”—is a joke that has been printed on many images. “Did you know that diarrhea is hereditary? It runs in your jeans” was posted on the newsgroup alt.surfing on October 30, 1991.
 
           
Google Groups: alt.surfing
Shit !!!
Nigel Brendon Robinson
10/30/91
(...)
Did you know that diarrhea is hereditary?
 
It runs in your jeans.
     
Google Groups: rec.humor
MORE GRAFITTI
P.M.Sriram
8/9/93
(...)
diarrhea is hereditary—- it runs in ur jeans!!!!
 
Google Groups: alt.fan.amy-fisher
who is Amy Fisher?
.(JavaScript must be enabled to view this email address)
4/20/94
(...) 
Diarrhea is hereditary—It runs down your jeans.
 
7 February 1998, New Brunswick Telegraph Journal (Saint John, NB), “My inheritance” by Herb Curtis:
“You could do worse. Did you know that diarrhea is hereditary?” he asked with a twinkle in his eye.
 
“No, I didn’t know that.
 
“Oh yes. It runs in your jeans.
     
Google Groups: alt.games.quake3
OT: Did you know that diarrhea is hereditary?
Greger Hoel
5/5/02
It runs in your genes.
 
Google Books
A Treasury of Gross Jokes
By Julius Alvin
New York, NY: Kensington Books
2003
Pg. ?:
How do you know that diarrhea is hereditary? It runs in your jeans.
   
Twitter
wilcolley‏
@wilcolley
Apparently diarrhea is hereditary, it runs in ur jeans ha ha ha
2:19 PM - 7 Sep 2008
 
Twitter
Bad Joke Cat‏
@BadJokeCat
Diarrhea is hereditary, it runs in your jeans.
3:30 PM - 15 Jan 2013
 
Google Books
Very Dirty Jokes For Adults
By Peter Crumpton
PeteyRF Creative
2014
Pg. ?:
Diarrhea is hereditary, it runs in your jeans.
     
Reddit—Jokes
Did you know that diarrhea is hereditary?
submitted December 12, 2015 by IsNotACleverMan
It runs in your jeans.
 
Reddit—Jokes
Did you know that diarrhea is hereditary?
submitted July 23, 2016 by SockMonkeyKing
It runs in your genes.
 
Reddit—Jokes
Did you know diarrhea is hereditary?
submitted September 29, 2017 by anonyaccty
Yep, it runs in your jeans