The present invention relates to methods of genotyping for selecting an animal with a desired trait such as the level monounsaturated fats in muscle tissue, the types and/or ratio of different monounsaturated fats in muscle tissue, marbling, carcass weight, meat quality, speed of finishing, feedlot efficiency and/or consumer preference. In particular the invention relates to methods of selecting an animal with a desired trait by analysing the M-RIP, NT5M and/or TCAP genes for one or more polymorphisms.