Mutation detection with SSCP and sequence electropherograms of p66Shc. PCR-SSCP and sequence analysis of the regulatory region of p66Shc locus (A) and of the p66Shc specific region CH2 (B). In the sequence electropherograms, arrows indicate the nucleotide substitution in heterozygous subjects as shown by the presence of the 2 superimposed peaks representing the normal and abnormal base. A) SSCP analysis of the 5' regulatory region of p66 locus (T/T subjects with wild-type sequence, T/C subjects heterozygous for the variant). B) SSCP analysis of the CH2 region: the 92C>T substitution consisted in an amino acid substitution P31L (C/C subjects with wild-type sequence, C/T subject heterozygous for the variant).