Heterozygous rhymes with:
homozygous, homozygous, vigus, analogous, angus, argus, asparagus, batuigas, baugus, bodegas, boggus, bogus, cunnilingus, degas, distrigas, esophagus, fergus, fungus, gargus, gregus, hargus, hillegass, hingis, homologous, homozygous, hugus, humongous, kilgus, landsbergis, las-vegas, las_vegas, lingus, lycurgus, margus, megace, negus, noriegas, ortegas, rogus, ruhrgas, sarcophagus, sprogus, tsongas, tsongas', vargas, vegas, vigus, wielgus, wilgus
Heterozygous sounds like:
haters, hatrick, hatteras, headdress, headdresses, headers, headrick, headwaters, heaters, heather's, heathers, heathrow's, hedrich, hedrick, heidrich, heidrick, heterosis, hetrick, hettrick, hitters, hooters, hydras, hydrick, hydro's, hydrous, hydrox, hydroxy