Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) has been used as a rapid method for the detection of human genetic polymorphisms. In particular, the mutations in the human HEXA gene that cause the infantile Tay-Sachs disease have been studied using MALDI-MS to demonstrate the feasibility of this technique for use in clinical and diagnostic analysis. The protocols involved in this approach include, polymerase chain reaction for the amplification of the mutation site from buccal cell DNA, followed by restriction enzyme digestion of the amplified regions of the template cells. The products of amplification and digestion were studied using MALDI-MS. MALDI-MS experiments are shown to provide essentially the same information as obtained from gel electrophoresis but orders of magnitude faster.