Hachiro Nakajima

Group-specific component (Gc) polymorphism in Japanese: An analysis by isoelectric focusing on polyacrylamide gels

SummaryUsing the immunofixation isoelectric focusing method, Gc subtypes were examined in the samples with the Gc J phenotypes previously determined by immunoelectrophoresis, and it was found that the GcJs are subdivided into 4 different alleles. A population study in sera from 1,041 individuals confirmed the presence of the 4 variant alleles with the frequencies between 0.020 for the highest allele and 0.001 for the lowest one. The distribution of Gc subtypes in a Japanese population and a pedigree study from 18 families with the propositus of the variant are presented along with a description of the 2 other variants observed in the course of this study.

A case report of a patient with retinoblastoma and chromosome 13q deletion: assignment of a new gene (gene for LCP1) on human chromosome 13

SummaryRetinoblastoma (Rb) occurs in hereditary, non-hereditary, and chromosomal deletion forms and the locus for the Rb gene (Rb-1) is closely linked to the locus for esterase D (ESD) assigned to the chromosome 13q14.11. We describe a patient who was predicted to have Rb from the genetic analysis of the chromosome and ESD phenotype. Furthermore, the gene for lymphocyte cytosol polypeptide with molecular weight of 64,000 (LCP1: McKusick catalogue No. 15343, 1983) was assigned to chromosome 13 by deletion mapping. A 3-month-old female had many characteristics of chromosome 13q-syndrome, including dolichocephaly, epicanthus, ptosis, depressed nasal bridge, micrognathia, short webbed neck, and short fifth fingers with clinodactyly and single crease. The karyotype of the patient was 46,XX,del(13) (q14.1–q32), though both the parents had normal karyotypes. As expected, the phenotype of ESD derived from one of the parents, the father in this case, was not detected in peripheral blood lymphocytes by two-dimensional gel electrophoresis (two-DE), indicating that ESD from the father was deleted in the abnormal chromosome 13. The possibility of paternity was calculated to be 0.996 based on the data using 22 genetic markers. Bilateral retinoblastomas could be diagnosed by ophthalmologic examinations before the manifestation of any clinical signs of the tumor and immediately intensive care was taken. In addition, the phenotype of LCP1 derived from the father was not expressed in the lymphocyte proteins from the patient. These data indicate that the gene for LCP1 (LCP1) is located in the region q14.1–q32 of chromosome 13 and may be a useful genetic marker for preclinical diagnosis of Rb.

Haplotype analysis of the linkage group HLA-A: HLA-B: Bf in Japanese

SummaryThree hundred four HLA-A: HLA-B: Bf haplotypes of the Japanese population as deduced by family analysis are described. Several linkage disequilibriums were observed in the following two-factor haplotypes: HLA-A and HLA-B, HLA-A and Bf, and HLA-B and Bf. Positive linkage disequilibriums between HLA-A and HLA-B noted in the present study seem to be Japanese specific when compared with the results obtained from other ethnic groups reported so far.The striking finding is that three HLA-B: Bf haplotypes, namely B12-BfF, B15-BfF,and B7-BfS,are common and show linkage disequilibrium in both Japanese and European Caucasians (German). This finding not only confirms the proximity of the HLA-B and Bf loci but also suggests that the interaction of the two genes plays an important role in the maintenance of stable linkage disequilibrium.

Human-type ABO, MN, and Lewis blood groups, and Gm and Inv factors in several species of macaques

More than 1,000 blood samples were collected from macaques of speciesM. fuscata, M. cyclopis, M. irus, M. mulatta, M. nemestrina, andM. speciosa, and all or a part of them were tested for human-type ABO, MN, and Lewis blood groups, and Gm and Inv factors. Differences between and/or within species analogous to racial differences in man were markedly noted in the distribution of the ABO and Lewis blood groups. Saliva samples from a small number ofM. fuscata were tested quantitatively for the presence of H and Lewis substances, and it was found that almost all the animals were secretors of H, Lea, and Leb, independently of the Lewis blood groups of their red cells. Red cells of all macaques tested contained M or M-like, but not Nv(V), antigens, and no polymorphism of MN blood groups was present. Selected plasma samples fromM. fuscata, M. cyclopis, M. irus, andM. nemestrina were found to be negative for all Gm(1), Gm(2), Gm(4), and Inv(1) factors tested.

Popliteal artery entrapment syndrome of the monozygotic twin —A case report and pathogenetic hypothesis—

A 22 year old Japanese man with popliteal artery entrapment syndrome in which both popliteal arteries were segmentally occluded and deviated medially, underwent surgical treatment by grafting and patching with autologous veins. His identical co-twin was also found to have a less severe form of popliteal artery entrapment syndrome. This is the first report of popliteal artery entrapment syndrome presenting in a pair of monozygotic twins and the concordance of the syndrome suggests that genetic factors may play a part in the development of this rare syndrome.

A case of maternity testing: Exclusion by polymorphic VNTR markers of DNA

SummaryThe genetic markers of a Korean woman and her allegedly adopted child were compared to test her maternity. None of 21 conventional markers, including 8 red cell antigens, 6 red cell enzymes, and 7 serum proteins, excluded the maternity. These results indicate a maternal probability of 0.31 which was too low to conclude the true maternity. Human leukocyte antigen (HLA)-A,-B,-C and-DR haplotyping was also uninformative in this case. The maternity was consequently excluded by the observation of a difference in 2 of 5 variable number of tandem repeat (VNTR) markers.

Group-specific component (Gc) polymorphism in Japanese: An investigation on the phenotypic distribution with regard to theGcJ allele

SummaryUsing the prolonged immunoelectrophoresis, Gc determination was performed in 1,347 plasma collected from 3 local populations in Japan. Six phenotypes determined by the codominant alleles, Gc1, Gc2 and GcJ, were observed, in which a new phenotype GcJ-J was included. This study revealed the presence of at least 3 polymorphic alleles at Gc locus in Japanese population.

Genetic polymorphism of the fourth component of human complement in Japanese

SummaryPolymorphism of the fourth component of human complement (C4) was investigated in Japanese using an agarose gel electrophoresis and a slab polyacrylamide gel electrophoresis followed by immunofixation. Three common phenotypes were observed corresponding to the types F, FS and S reported in Europeans. Typing of the family material consisting of 48 matings with 96 offsprings showed no discrepancy from the postulate that C4 polymorphism is controlled by a pair of codominant alleles. In a sample from 291 unrelated healthy Japanese, the allele frequencies of C4F and C4S are estimated at 0.543 and 0.457, respectively.

Human-type blood groups and Gm factors in gibbons (Hylobates)

Blood specimens from 69 gibbons (63Hylobates lar, 4Hylobates concolor, and 2Hylobates pileatus) were tested for human-type ABO, MN, and Rh blood groups. AmongH. lar, three phenotypes were noted in the ABO and MN blood groups respectively, but all fourH. concolor were grouped as AM. All group A gibbons were of subgroup A1; subgroups A2B and A1⋅2B were observed at a low frequency in group AB gibbons. Leb antigen was detected in about 30% of the red cell samples fromH. lar, but all the samples were negative for Lea. All the gibbons tested had c(hr′) antigen but no other Rh antigens (D, C, E, and e) in their red cells. Some selected blood samples fromH. lar were also tested for some other blood group antigens and for the Gm and Inv factors. The Jka antigen was detected in all the red cell samples tested, but the S, s, U, K, k, and Fya antigens were not. In the tests of plasma with anti-Gm (1),H. lar could be divided into two groups, i.e., Gm(1)Gi and Gm(−1)Gi; Gm(2), Gm(4), and Inv(1) were absent in the species.

Haplotype analysis of the linkage group HLA-A∶HLA-B∶C4 in Japanese: Evidence for the C4 locus being between the HLA-A and HLA-B loci

Summary176 HLA-A:HLA-B:C4 haplotypes of the Japanese population as deduced by family analysis are described. Four combinations between the HLA and C4 alleles, namely, B12-C4S, Bw54-C4F, Bw52-C4F and Aw33-C4S, are shown to be in significantly positive linkage disequilibrium. This finding suggests close proximity between the HLA-B and C4 loci. In a family with HLA-A:HLA-B recombinant, the evidence is presented indicating that the C4 allele travels with the HLA-A allele. Therefore, it is considered that the C4 locus is probably situated between the HLA-A and HLA-B loci.