A. Hirono et al., IDENTIFICATION OF 2 NOVEL DELETION MUTATIONS IN GLUCOSE-6-PHOSPHATE-DEHYDROGENASE GENE CAUSING HEMOLYTIC-ANEMIA, Blood, 85(4), 1995, pp. 1118-1121
Among over 50 distinct mutations causing glucose-6-phosphate dehydroge
nase (G6PD) deficiency, only two deletion mutations have so far been r
eported. Using nonradioisotopic single-strand conformation polymorphis
m analysis, we found two additional deletion mutations in two Japanese
G6PD-deficient patients with nonspherocytic hemolytic anemia, Case no
. 1 had a 3-nucleotide deletion in exon 6 predicting a deletion of a s
erine at amino acid 188 or 189, which caused a class 1 variant GGPD Ts
ukui, Case no, 2 had a 3-nucleotide deletion in exon 5 predicting a de
letion of a lysine at residue 95, which caused a class 2 variant G6PD
Urayasu. The 188th serine, which might be deleted in G6PD Tsukui, is l
ocated close to the putative G6P binding site, The 188th serine is als
o involved in the amino acid substitution in G6PD Mediterranean, but t
he kinetics of these two variants are totally different. The residue w
ith an amino acid deletion in G6PD Urayasu was distant from the substr
ate binding sites and was located in a region with low sequence homolo
gy among species. The different properties of variants having mutation
s in exons 5 and 6 suggest that these two exons code distinct function
al domains of the enzyme. (C) 1995 by The American Society of Hematolo
gy.