Danny_57, 02/04/2012 23.10:All comb type genes must be in their "original" form to have a single-comb (not only p+/p+ and r+/r+). d+/d+,r+/r+,p+/p+,Bd+/Bd+ = single-comb. This is right .... for single comb For the rose are three different genes - For there are comb Spyke studies?]