A. Hirono et al., A NOVEL HUMAN CATALASE MUTATION (358-T-]DEL) CAUSING JAPANESE-TYPE ACATALASEMIA, Blood cells, molecules, & diseases, 21(23), 1995, pp. 232-234
Japanese-type acatalasemia is characterized by the almost total loss o
f catalase activity in red cells and is often associated with ulcerati
ng oral lesions, A splicing mutation in intron 4 of the catalase gene
has so far been a sole disease-causing mutation found in Japanese-type
acatalasemic patients, we report here a novel single base deletion in
the catalase gene causing Japanese-type acatalasemia, The patient was
a 72-year-old Japanese male, His maternal grandmother and his father
were first cousins, Molecular analysis using non-RI PCR-SSCP analysis
combined with direct sequencing revealed a deletion of the 358th thymi
ne in exon 4 of the patient's catalase gene, The proband was a homozyg
ote and his mother and his three children were heterozygotes for this
mutation, The frame shift caused by the nucleotide deletion should alt
er the downstream amino acid sequence and introduce a new termination
codon TGA 43 bp 3' to the mutation, Although the truncated peptide cha
in consisted of 133 amino acid residues might be translated in the pat
ient's tissue, such an aberrant protein is expected to be extremely un
stable and have no catalytic function at all, Our results suggest that
Japanese-type acatalasemia is heterogeneous at molecular level.