Mikio Fujita

Electrophoretic variants of blood proteins in Japanese

SummaryA total of 15,387 individuals living in Hiroshima and Nagasaki, of whom 10,864 are unrelated, were examined for erythrocyte triosephosphate isomerase (TPI) by starch gel electrophoresis using TEMM buffer, pH 7.4. Four kinds of new variants, one having a cathodal migration and three having anodal migrations, were encountered in this population. These variants were further characterized by starch gel electrophoresis using tris-EDTA buffer, pH 9.3, and isoelectric focusing. An anodally migrating allozyme TPI 2HR1 exhibited markedly decreased enzyme activity, as evaluated by the staining intensity of the variant bands. The level of TPI activity in erythrocytes from this individual with the phenotype TPI 1-2HR1 was about 60% of the normal mean. Family studies confirmed the genetic nature of all the variants.

Heterozygosity and ethnic variation in Japanese platelet proteins

SummarySixty-two polypeptides visualized on silver-stained two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) preparations of platelets from 85 Japanese subjects, in total 5,252 spots, have been scored for genetic variation. Inherited variants of 11 of the polypeptides were recognized; the index of heterozygosity was 2.4%±0.2%. Thus far, 10 genetic polymorphisms identified by 2-D PAGE of plasma, erythrocytes, or platelets have been identified in both Japanese and Caucasian subjects. A comparison of allele frequencies reveals four significant ethnic differences. We also observed four polypeptides exhibiting a low frequency polymorphism in one group but not in the other, as well as three polymorphisms in Caucasians for which no counterpart polypeptide has thus far been recognized in the Japanese group and, vice versa, 11 such polymorphisms in Japanese. Although a similar comparison of 7 enzyme polymorphisms studied with one-dimensional electrophoresis (1-D E) in the same populations revealed a relatively higher number of significant ethnic differences, evidence is presented that this is due primarily to the greater number of 1-D E observations entering into the calculation. It is argued that this similarity in the frequency of ethnic differences among the polypeptides studied by 2-D PAGE and by 1-D E is further evidence that the proteins revealed by 2-D PAGE do not differ greatly in their response to the interplay of mutation, selection, and drift from those revealed by 1-D E studies of plasma proteins and erythrocyte enzymes.

Electrophoretic variants of blood proteins in Japanese I. Phosphoglucomutase-2 (PGM2)

SummaryA total of 17,126 individuals, of whom 11,833 are unrelated, living in Hiroshima and Nagasaki were examined for erythrocyte phosphoglucomutase-2 (PGM2) by starch gel electrophoresis using TEMM buffer, pH 7.4. Four kinds of hereditary rare variants were encountered, three detected in single families and the one remaining in 9 unrelated families. In addition, a fresh mutant whose main band migrated slightly cathodal to the d-band was detected in a male child in Nagasaki, whose parents were proximally exposed to the atomic bomb in that city. The results described here confirm our previous data that PGM2 variation is quite low among the Japanese.

Inherited thermostability variants of seven enzymes in a Japanese population

The frequency of inherited variations in thermostability was investigated in a series of seven enzymes in a Japanese population. Among a total of 5930 determinations, nine variants were encountered. In each instance one parent exhibited a similar finding. It is suggested that this procedure should detect a high proportion of the variants of these enzymes characterized by amino acid substitutions not altering molecular charge. Failure to detect more such thermostability variants is interpreted to mean that electrophoresis not only detects amino acid substitutions altering molecular charge but also a considerable proportion of those that do not alter charge.

Electrophoretic variants of blood proteins in Japanese VI. Transferrin

SummaryA multiplicity of transferrin variants have been detected in the course of the biochemical aspect of the study of the genetic effects of atomic bombs. Variants obtained from the studies of 19,770 individuals in Hiroshima and Nagasaki were compared by polyacrylamide slab gel electrophoresis using three kinds of buffer systems with different pH values and thin layer polyacrylamide gel isoelectric focusing. The variants were compared on the basis of their relative mobilities and isoelectric points; seven types of fast-moving variant (B-variant) and nine types of slow-moving variant (D-variant) were detected, involving a total of 154 and 273 individuals, respectively. All the variants were identified as genetic variants by family studies. No variant differend inaallele frequency between the two cities. The variants detected in this study were compared with variants detected in residents of Mie district (another Japanese population), Caucasoids, American blacks, and Amerindians. Six additional types of B-variant and four additional types of D-variant, which had not been detected in Hiroshima and Nagasaki, were identified.

Electrophoretic variants of blood proteins in Japanese. IV. Prevalence and enzymologic characteristics of glucose-6-phosphate dehydrogenase variants in Hiroshima and Nagasaki

SummaryElectrophoretic screening of glucose-6-phosphate dehydrogenase (EC 1.1.1.49, G6PD) was conducted one sample of 9,260 children born to the atomic bomb survivors in Hiroshima (Honshu) and Nagasaki (Kyushu). The prevalence of electrophoretic variants was 0.11% in males and 0.42% in females in Hiroshima, and 0.16% in males and 0.31% in females in Nagasaki. Enzymologic characteristics of 10 variants obtained from three males and seven hemizygous fathers of heterozygous females were examined. As a result, three new types of G6PD variants were identified among five variants detected in Hiroshima, and three new types among five variants in Nagasaki. All the variants except one belonged to Class 3, as defined by Yoshida et al. (1971).

Electrophoretic variants of blood proteins in Japanese VII. Cytoplasmic glutamate-oxaloacetate transaminase (GOT1)

SummaryA total of 16,835 children, of whom 11,737 are unrelated, from Hiroshima and Nagasaki were examined for erythrocyte cytoplasmic glutamate-oxaloacetate transaminase (GOT1) by starch gel electrophoresis. A variant allele named GOT1* 2HR1 which seems to be identical with GOT1*2 was encountered in polymorphic frequency. Five kinds of rare variants, 3NG1, 4NG1, 5NG1, 6HR1 and 7NG1 were encountered in a total of 109 children. Except for 7NG1 for which complete family study was unable, family studies confirmed the genetic nature of these rare variants, since for all instances in which both parents could be examined, one of the parents exhibited the same variant as that of their child. Thermostability profiles of these six variants were normal. The enzyme activities of five were decreased, while the value of one was normal compared to that of GOT1 1.

Electrophoretic variants of blood proteins in Japanese V. Ceruloplasmin

SummaryThe plasma ceruloplasmin of 22,367 children of A-bomb survivors in Hiroshima and Nagasaki was examined for variants by electrophoresis. The sample was composed of 14,964 unrelated children and 7,403 siblings of the unrelated persons. A total of seven types of electrophoretic variants were detected; four migrating anodally and three cathodally to the normal B band. We have reported two of these variants, CP ANG1 and CP CNG1, previously but the other five, CP ANG2, CP AHR1, CP AHR2, CP CHR1, and CP CHR2, are newly identified. The allelic frequency of CP*CNG1 was 0.00916, so that the variant is considered to be a polymorphic allele. Homozygosity for the CP*CNG1 allele was detected in five individuals. This is the first report of a homozygous phenotype for a ceruloplasmin variant in a Japanese population. Family study of the new five variants all demonstrated patterns of codominant inheritance.

Variants of red Cell Enzymes Found in Japanese of Hiroshima and Nagasaki

In the course of our search for possible genetic effects of radiation among the children of A-bomb survivors in Hiroshima and Nagasaki, we have obtained considerable electrophoretic data which clearly illustrate some of the genetic characteristics of the populations of both cities, which characteristics, however, have no relationship with radiation exposure of the parents. The frequencies of variants of phosphoglucomutase1 (PGM1) and glucose phosphate isomerase (GPI) were observed to be significantly higher in Nagasaki than in Hiroshima. As the difference in the frequencies of transferrin variants between two cities are also significant, it is apparent that the populations of the two cities are genetically different with respect to variation in certain protein systems.