Gene analysis of genomic DNA from stored serum by polymerase chain reaction: identification of three missense mutations in patients with cholinesterasemia and ABO genotyping

We established a method to determine the butyrylcholinesterase genotype associated with a BCHE deficiency directly using multiple PCR from stored serum, which was stored at −70°C for more than 30 years. PCR products from sera of six propositi were used for DNA sequence analysis. All of these BChE variants were characterized by a single nucleotide substitution. Four of them were homozygotes and demonstrated a C→T single nucleotide point mutation at codon 100 from CCA (Pro) to TCA (Ser). The fifth case was a heterozygote of this mutation. The remaining one was a compound heterozygote showing a T→C transition mutation at codon 203 from TCA (Ser) to CCA (Pro) and a G→C transversion mutation at codon 365 from GGA (Gly) to CGA (Arg). Furthermore we developed a method to determine the ABO genotype from the same serum. These results indicated that serum is useful as a starting material for amplification of genomic DNA when fresh blood samples are not available.