 " Lisa the Simpson " is the seventeenth episode of The Simpsons 's ninth season . It originally aired on the Fox network in the United States on March 8 , 1998 . In the episode , Lisa fears that she may be genetically predisposed to lose her intelligence after Grandpa tells her of a family gene that can permanently take away intelligence . 
 " Lisa the Simpson " <a href='drop_aux' title='1'><mark>is</mark></a>the seventeenth episode of The Simpsons <a href='null_genetive' title='2'><mark>'s</mark></a>ninth season . It originally aired on the Fox network in the United States on March 8 , 1998 . In the episode , Lisa <a href='uninflect' title='3'><mark>fears</mark></a> that she may be genetically predisposed to lose her intelligence after Grandpa <a href='uninflect' title='4'><mark>tells</mark></a> her of a family gene <a href='null_relcl' title='5'><mark>that</mark></a>can permanently take away intelligence . 
 Lisa the Simpson  the seventeenth episode of da Simpsons  ninth season . It originally aired on the Fox network in the United States on March 8 , 1998 . In the episode , Lisa fear dat she may be genetically predisposed to lose her intelligence after Grandpa tell her of a fam gene can permanently take away intelligence .