Single-strand conformation polymorphism (SSCP) analysis detects mutations based on the fact that single-nucleotide changes in DNA sequences alter the mobility of single-stranded DNA in nondenaturing gels. Four methods for detecting mutations based on SSCP are described here. (1) Traditional SSCP analysis is technically easy and can be used for screening large numbers of samples. SSCP-hybrid methods detect mutations based on either an SSCP effect or an altered component independent of the SSCP effect. (2) Dideoxy fingerprinting (ddF) involves PCR amplification of the target and creation of a set of dideoxy-terminated strands with the mutation. (3) Bi-directional dideoxy fingerprinting (Bi-ddF) involves production of two sets of dideoxy-terminated strands that are generated from two different primers. (4) Restriction endonuclease fingerprinting (REF) involves cleavage of the amplified target with five to six groups of restriction endonucleases.