Fig. 3.

Mutation Arg528Gly of the CACNA1S gene co-segregates with HypoPP in the family. Marker 100-bp molecular weight ladder/ marker (Invitrogen), N normal phenotype, P affected phenotype. The sample lanes are labeled with the unique identification numbers for each individual in the Chinese family with HypoPP as in Fig. 1, e.g. I-1 is for individual 1 at generation I in Fig. 1. The Arg528Gly mutation abolishes an MspA1 I site. The wild type PCR product can be cut by MspA1 I, yielding two shorter DNA fragments of 252 and 112 bp. Normal family members display two 252 and 112 bp bands except for the two female individuals III-1 and III-3 (marked with N*) who show reduced penetrance. The PCR fragment containing mutation Arg528Gly cannot be cut by the enzyme, resulting in only one DNA fragment of 364 bp. All affected individuals in the family are heterozygous for the Arg528Gly mutation (three fragments: 364, 252, and 112 bp). the PCR primers used were: 528-1 forward, 5′-AAGGCTGGGAGTCAGGAGAAG-3′ and 528-1 reverse, 5′-ATGAGATGGGTGTAGACCAGAC-3′