WordNet (r) 3.0 (2006):

genetics
    n 1: the branch of biology that studies heredity and variation
         in organisms [syn: genetics, genetic science]

Moby Thesaurus II by Grady Ward, 1.0:

77 Moby Thesaurus words for "genetics":
   Altmann theory, DNA, De Vries theory, Galtonian theory,
   Mendelianism, Mendelism, RNA, Verworn theory, Weismann theory,
   Weismannism, Wiesner theory, aerobiology, agrobiology, allele,
   allelomorph, anatomy, astrobiology, bacteriology, biochemics,
   biochemistry, biochemy, bioecology, biological science, biology,
   biometrics, biometry, bionics, bionomics, biophysics, birth,
   botany, cell physiology, character, chromatid, chromatin,
   chromosome, cryobiology, cybernetics, cytology, determinant,
   determiner, diathesis, ecology, electrobiology, embryology,
   endowment, enzymology, ethnobiology, eugenics, exobiology, factor,
   gene, genesiology, genetic code, gnotobiotics, hereditability,
   heredity, heritability, heritage, inborn capacity, inheritability,
   inheritance, life science, matrocliny, microbiology,
   molecular biology, patrocliny, pharmacogenetics, pharmacology,
   physiology, radiobiology, recessive character, replication,
   taxonomy, virology, xenobiology, zoology