What is the connection between Tom and Gatsby?

The most obvious connection between Tom and Gatsby is
Daisy.  Tom  is married to Daisy, but shows little affection towards her.  Gatsby is
madly in love with her despite the fact that she is a married woman.  Tom buys an
apartment in the city to get away from Daisy with his mistress.  Gatsby buys a mansion
across the harbor to be close to Daisy.  He throws elaborate parties in the hopes that
she will wander in. 

Another connection between the two is the death
of Gatsby.  Tom's mistress is killed in a car accident and Tom convinces her husband
that it was Gatsby.  He persuades her husband that Gatsby was her lover instead of him. 
Her husband then goes looking for revenge and kills Gatsby.