Original: Genetics ( from Ancient Greek , '' genitive '' and that from , '' origin '' Genetikos , Henry George Liddell , Robert Scott , '' A Greek-English Lexicon '' , at PerseusGenesis , Henry George Liddell , Robert Scott , '' A Greek-English Lexicon '' , at PerseusOnline Etymology Dictionary ) , a discipline of biology , is the science of genes , heredity , and variation in living organisms .
Simplified: The word comes from the Ancient Greek for origin It is the science of heredity and variation of traits ( characteristics ) in living organisms , and the study of genes .