Biomedical subjects

K Fujiki

Publications and source records attributed to K Fujiki.

112 records · Page 7Linked to original sources

PubMedDate not supplied

Multicenter genetic study of retinitis pigmentosa in Japan: II. Prevalence of autosomal recessive retinitis pigmentosa.

Retinitis pigmentosa (RP) is a group of genetically heterogeneous diseases with autosomal recessive (AR), autosomal dominant, and X-linked modes of inheritance. Autosomal recessive retinitis pigmentosa (ARRP) is the most common form in Japan. A genetic analysis was done to determine the prevalence of ARRP indirectly, to provide an estimation of changing trends in the overall prevalence of RP. Data on the frequency of consanguinity and marriage year of normal parents of 59 ARRP patients were obtained from a nationwide multicenter survey of typical retinitis pigmentosa conducted in 1990. The gene frequency of ARRP was 0.01145 (Dahlberg's formula). In 1990, the number of young symptomatic ARRP patients decreased, while the number of patients aged 40 years and older increased. The total number of symptomatic ARRP patients in 1990 was nearly 21% higher than in 1970. Despite a dramatic decline in consanguinity in recent decades in Japan, the number of ARRP patients has increased. This increase is attributed to greater longevity and overall population growth. Our results suggest that the total number of RP patients has not decreased, and may even have increased.

Adolescent↗

PubMedDate not supplied

Plus/minus screening of rabbit corneal endothelial cDNA library.

Plus/minus screening of the rabbit corneal cDNA library was performed using corneal and iris RNA as probes. Thirteen clones were isolated: three ferritin H-chains, a NADH-ubiquinone oxidoreductase B22 subunit, an alpha 1 type VIII collagen, a 25 KDa FKBP-506 binding protein (FKBP25), a thrombospondin 2, and six unknown clones. Although proteins translocated from these isolated mRNA are not corneal specific, they play an important role in the cornea. None of the isolated known mRNAs maps to chromosome 1, 16, or 20. These clones, thrombospondin excepted, were not observed in the high frequency clones in the profile of the aortic endothelial cDNA library.

Amino Acid Sequence↗

PubMedDate not supplied

Analysis of peripherin/RDS gene for Japanese retinal dystrophies.

We studied 133 Japanese patients with retinal dystrophies to detect peripherin/RDS (retinal degeneration slow) gene defects. The patients analyzed included 52 with autosomal dominant retinitis pigmentosa, 36 with autosomal recessive retinitis pigmentosa, 3 with simplex retinitis pigmentosa, 12 with cone-rod dystrophy, 5 with rod-cone dystrophy, 3 with vitelliform macular dystrophy (Best's disease), 4 with macular dystrophy, 2 with cone dystrophy, 2 with fundus flavimaculatus, 2 with fundus albipunctatus, and 12 with retinitis pigmentosa with macular degeneration as well as 40 unrelated normal persons. Three exons of the peripherin/RDS gene cut into 150-200 base-pair fragments were amplified by polymerase chain reaction and screened by single-strand conformation polymorphism. The DNA fragments with any suspected variations were directly sequenced. Eight point mutations were detected. Among them, two missense mutations at codons 304 and 338 result in an amino acid substitution of glutamine for glutamic acid and aspartic acid for glycine, respectively. However, they were not cosegregated with the diseases, and these mutations were also commonly found in normal controls. For these controls, the proportion of transversion from G to C at codon 304 (GAG-->CAG) and transition from G to A at codon 338 (GGC-->GAC) were 0.192 +/- 0.045 and 0.173 +/- 0.053, respectively. Our results suggest that a peripherin/RDS gene mutation might be rare in Japanese patients.

DNA↗

PubMedDate not supplied

Arg124Cys mutation of the betaig-h3 bene in a Japanese family with lattice corneal dystrophy type I.

To characterize severe lattice corneal dystrophy, we analyzed the betaig-h3 gene, clinical features, histological findings, and genotype-phenotype correlation in an affected Japanese family. Deoxyribonucleic acid was extracted from leukocytes in 16 members (12 affected and 4 unaffected) of a Japanese family with lattice corneal dystrophy type I. Exon 4 of the betaig-h3 gene was amplified and analyzed using molecular biological methods. Clinical and pathological data were also collected. We found a heterozygous point mutation that causes the disease phenotype. It was a single base-pair transition leading to an amino acid substitution (CGC-->TGC, Arg124Cys). The phenotypic variation within families was not recognized. The affected members in the pedigree demonstrated severe visual disturbance in the third decade and required keratoplasty. Histopathological examination revealed amyloid deposits consisting of short and thin amyloid fibers and lattice corneal dystrophy type I. The heterozygous Arg124Cys mutation reported in Caucasian lattice corneal dystrophy caused severe lattice corneal dystrophy consisting of short and thin amyloid fibers in a Japanese family. Based on our study of many members of the family, we are able to construct the natural course of this disorder from its earliest clinical findings through its late manifestations.

Adult↗