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Isao Yuasa

Publications and source records attributed to Isao Yuasa.

18 recordsLinked to original sources
PubMed2006

Variation of interleukin 8 -251 A>T polymorphism in worldwide populations and intra-ethnic differences in Japanese populations.

BACKGROUND: Interleukin-8 (IL8) is a member of the family of chemokines. The IL8 gene has polymorphic variations, and the genotype of IL8 -251 A>T is associated with smoking behavior and cancer progression. METHOD: IL8 -251 A>T polymorphism were investigated in Japanese, from 5 different areas, in Ovambo, Turkish, Mongolian and Korean populations by PCR with confronting 2-pair primers (PCR-CTPP) analysis. RESULTS: A subpopulation analysis of Japan revealed a north-to-south increase in the frequency of the IL8 -251 T allele. Among the 5 groups, the Japanese showed the highest frequency of mutant allele followed by the Turks. The distribution pattern in the Japanese was different from those of Mongolians and Koreans. In the Ovambo population, no mutant allele homozygote subject was found and the frequency of mutant alleles was the lowest, similar to that in Gambians. CONCLUSION: The present study is the first to demonstrate the Japan population inter-prefecture differences in IL8 -251 A>T polymorphism as well as a certain genetic heterogeneity in the worldwide distribution of IL8 -251 A>T polymorphism. The distribution results may help define the true significance of IL8 -251 A>T polymorphism as a marker for smoking behavior in populations worldwide.

Adenine↗
PubMed2006

Origin and evolution of gene for prolactin-induced protein.

Prolactin-induced protein (PIP) is a small protein secreted into the fluid in several glands. We determined the PIP coding sequences of 5 hominoid species and estimated the numbers of synonymous and nonsynonymous substitutions for each branch of the mammalian PIP gene tree. The branch connecting hominoids and Old World monkeys showed significantly higher nonsynonymous than synonymous substitutions. These changes tended to be accumulated in the fibronectin-binding domain. Many other primate branches also showed higher nonsynonymous than synonymous substitutions, thus suggesting that the PIP genes of primates have experienced some kind of positive selection. We also considered the phylogenetic relationship of the PIP gene with the alpha-2-macroglobulin gene family. The results indicate that the PIP gene arose by partial gene duplication from a member of the alpha-2-macroglobulin gene family after the divergence between amphibians and other tetrapods.

Amino Acid Sequence↗
PubMed2006

The structure and diversity of alpha1-acid glycoprotein/orosomucoid gene in Africans.

Human orosomucoid (ORM), or alpha(1)-acid glycoprotein, is known to be controlled by duplicated and triplicated genes on chromosome 9, encoding ORM1 and ORM2 proteins. In this study, the structure and diversity of the ORM gene were investigated in 16 Sub-Saharan Africans, who originated from widely dispersed locations in Africa. The duplicated ORM1-ORM2 gene was observed in all 16 samples. ORM1*S1(2), characterized by an ORM2 gene-specific sequence in intron 5, was common in Africans. Three Africans showed the duplication of the ORM1 gene. The organization of the triplicated ORM1A-ORM1B-ORM2 gene was established in two Africans. The recombination breakpoints resulting in the ORM1 duplication lay within a small genomic interval around exon 1 of the ORM1B gene. The duplication of the ORM2 gene reported previously was not detected in this population sample. Several single-nucleotide polymorphisms were observed in the ORM2 gene. The rearrangement of the ORM gene is likely to occur often in Africans.

Alu Elements↗
PubMed2006

Parentally imprinted allele typing at a short tandem repeat locus in intron 1a of imprinted gene KCNQ1.

A short tandem repeat (STR) in the intron 1a of paternally imprinted gene, KCNQ1, is evaluated as a new probe for use in parentally imprinting allele (PIA) typing. This typing can determine the inheritance of one allele from father by the methylation difference. Allelic and genotypic frequencies of the STR were determined using samples from 175 unrelated Japanese and 170 unrelated Germans. The polymorphism information contents were 0.652 and 0.634 for the Japanese and the Germans, respectively, indicating usefulness in individual identification. This method was applied to five Japanese families consisting of 19 individuals. Genomic DNA was digested by methylation-sensitive restriction endonucleases, HhaI and HapII, followed by PCR amplification using two-step sandwich primer sets and the products were analyzed on polyacrylamide gel electrophoresis. For all of the families, each child's paternal allele given by PIA typing corresponded to one of the two alleles from father, not the two from mother, that were determined by the STR genotyping. The results demonstrate that this STR probe is feasible for use in PIA typing and that its typing method can contribute to paternity testing.

DNA Probes↗
PubMed2006

Monozygotic twins discordant for Klippel-Feil syndrome.

In a pair of Japanese monozygotic twins, one manifested Klippel-Feil syndrome, a short neck with C(1-4) vertebra fusion, whereas the other was normal. The discordance between the twins suggests that Klippel-Feil syndrome results in part from a postzygotic somatic mutation or intrauterine environmental factors.

Diseases in Twins↗
PubMed2005

Multiplex amplified product-length polymorphism analysis of 36 mitochondrial single-nucleotide polymorphisms for haplogrouping of East Asian populations.

We present a reliable, rapid, and economical multiplex amplified product-length polymorphism (APLP) method for analyzing the haplogroup-diagnostic mitochondrial single-nucleotide polymorphisms (mtSNPs) in East Asian populations. By examining only 36 haplogroup-specific mtSNPs in the coding region by using four 9-multiplex polymerase chain reaction (PCR) and subsequent electrophoresis, we could safely assign 1815 individuals from 8 populations of Japanese, Korean, Chinese, and Germans to 45 relevant haplogroups. This multiplex APLP analysis of coding-region mtSNPs for haplogrouping is especially useful not only for molecular phylogenetic studies but also for large-scale association studies due to its rapid and economical nature. This is the first panel of mtSNPs in the coding region to be used for haplogrouping of East Asian populations.

Asian People↗
PubMed2005

Molecular aspects of biochemical markers.

This review summarizes present knowledge of the molecular basis for certain serum protein and red cell enzyme markers that have played important roles in forensic individualization and paternity tests. Most genes have nucleotide variations at two or more mutations sites, and their alleles exist as haplotypes. Allelic diversity is generated by various mechanisms including point mutation, intragenic recombination, gene conversion, and alternative splicing. Deficient and null alleles arise from point mutation and deletion. The value of genomic information on allelic diversity is also discussed.

Crossing Over, Genetic↗
PubMed2005

Recent progress in mitochondrial DNA analysis.

In this review, we describe the current state of knowledge of mitochondrial genetics of East Asian populations and its application to forensic science. Recent advances in mitochondrial DNA (mtDNA) phylogeny have identified haplogroup-specific single nucleotide polymorphisms (SNPs) and the control region motifs of haplogroups. By analyzing haplogroup-specific SNPs, we can rapidly and accurately connect the mtDNA under study to the relevant haplogroup. Haplogroups are fairly continent- and/or region-specific; therefore, we can infer the ethnic background of that mtDNA. In addition, errors in hypervariable region sequences can be detected by means of haplogroup motif analysis.

Animals↗
PubMed2005

Association of functional gene polymorphisms of matrix metalloproteinase (MMP)-1, MMP-3 and MMP-9 with the progression of chronic liver disease.

BACKGROUND AND AIMS: Matrix metalloproteinases (MMP) play an important role in the progression of liver fibrosis in addition to fibrogenesis. MMP-1, MMP-3, and MMP-9 gene polymorphisms have been shown to influence the transcriptional activity of their respective gene promoter in an allele-specific manner. The aim of this study was to examine the possible association of MMP-1, MMP-3, and MMP-9 gene polymorphisms with the progression of chronic liver disease in the Japanese population. METHODS: We examined 91 patients with HCV-related chronic hepatitis and 89 patients with HCV-related liver cirrhosis. We determined MMP-1 1G/2G, MMP-3 5A/6A, and MMP-9 C/T polymorphisms using polymerase-chain reaction based assays. RESULTS: In MMP-1 genotypes, the 2G homozygotes were significantly more in cirrhotic group than in chronic hepatitis group. In MMP-3 genotypes, there were no significant differences in genotype distributions and allele frequencies between chronic hepatitis and liver cirrhosis groups. However, 5A carriers had a significantly lower age at liver cirrhosis diagnosis and a higher Child-Pugh score compared with the 6A homozygotes. In MMP-9 genotypes, the C homozygotes and C allele frequencies were significantly more in liver cirrhosis group than in chronic hepatitis group. CONCLUSION: These findings suggest that MMP-1, MMP-3, and MMP-9 gene polymorphisms account for some of the variability in the progression of HCV-related chronic liver diseases.

Aged↗
PubMed2004

MATP polymorphisms in Germans and Japanese: the L374F mutation as a population marker for Caucasoids.

Inference of the population and ancestry to which an individual belongs is important in forensic individualization and personal identification. In this study, five polymorphisms of the membrane-associated transporter protein (MATP) gene were investigated in German and Japanese populations. The L374F mutation was present at an allele frequency as high as 0.96 in the German population, whereas it was completely absent in the Japanese population. This extreme difference in allele frequency suggests that the L374F mutation is valuable as a population and ancestry informative marker for Caucasoids.

Antigens, Neoplasm↗
PubMed2004

A novel 56-bp variable tandem repeat polymorphism in the human deoxyribonuclease I gene and its population data.

This study confirms the presence of a novel variable number of tandem repeats polymorphism, designated as HumDN1, in intron 4 of the human deoxyribonuclease I (DNase I) gene. Genotyping was performed without difficulty by PCR-amplification and separation by agarose gel electrophoresis in 423 Japanese, originating from four geographically diverse areas in Japan, and 89 Germans. The HumDN1 allele variability was due to different numbers of 56-bp repeat sequences, and five different alleles were distinguished with apparent size between 364 and 588 bp. Although there was a general uniformity for the polymorphism in the Japanese population, significant differences in genotype distribution were found between the Japanese and German populations. Furthermore, linkage disequilibrium between the HumDN1 and DNase I protein polymorphisms was revealed.

DNA Fingerprinting↗
PubMed2004

Molecular basis of ESD*5 and ESD*7 and haplotype analysis with new polymorphisms in introns.

The two polymorphic alleles of esterase D (ESD), ESD*5 and ESD*7, are specific to Europeans and Asians, respectively. In this study the molecular basis was characterized: ESD*5, arising from ESD*1, has a G to A transition, resulting in Gly257(GGT) --> Asp(GAT); and ESD*7, originating from ESD*2, has an A to G transition, resulting in Asp231(GAT) --> Gly(GGT). Glycine is also involved in the common ESD*1/ESD*2 polymorphism [Gly190(GGA) --> Glu(GAA)]. Haplotype analysis using a few novel intragenic polymorphisms showed strong associations among polymorphic sites, suggesting that recombination has been less frequent in the human ESD gene, although it spans about 25 kb from exon 1 to exon 10. A marked difference was observed in the distribution of haplotype frequencies between Germans and Japanese.

Animals↗
PubMed2003

Novel nonsense mutation (R194X) in the PMM2 gene in a Japanese patient with congenital disorder of glycosylation type Ia.

A Japanese boy had clinical features of congenital disorder of glycosylation type Ia (CDG Ia, also known as carbohydrate-deficient-glycoprotein syndrome, previously), and enzymatic and molecular assay of phosphomannomutase confirmed this diagnosis. During infancy, the patient showed delayed mental and motor development, hypotonia, ataxia, hepatomegaly, liver dysfunction, abnormal coagulation system and cerebellar hypoplasia. At present, though he is 3 years and 8 months old, he cannot utter meaningful words or sit by himself. These findings suggested that he had one of the severe phenotypes of Japanese CDG Ia. Mutational analysis demonstrated heterozygosity for the missense mutation in exon 4 (P113L) and a novel nonsense mutation in exon 7 (R194X). We report his clinical course and the results of molecular assay, and discuss correlation between clinical severity and genotype.

Codon, Nonsense↗
PubMed2003

Novel paternity testing by distinguishing parental alleles at a VNTR locus in the differentially methylated region upstream of the human H19 gene.

Conventional PCR-based genotyping is useful for forensic testing but cannot be used to determine parental origins of alleles in DNA specimens. Here we describe a novel method of combined conventional genotyping and PIA typing (parentally imprinted allele typing) at a minisatellite region upstream from the H19 locus. The PIA typing uses two sets of primers and DNA digested with methylation-sensitive Hha I enzyme. The first amplification produces only the methylated fragment of paternal H19 allele, and the second detects polymorphism in the minisatellite. Hence, this distinguishes paternal and maternal alleles by difference in the DNA methylation. Furthermore, the polymorphism in this polymorphic locus was examined using 199 unrelated Japanese and 171 unrelated Germans, their polymorphism information content being 0.671 and 0.705, respectively. Feasibility of this typing is demonstrated for six families, and the usefulness is shown by application to paternity testing.

Alleles↗
PubMed2002

Molecular analysis of the human esterase D gene ESD(*)Q0(yonago) responsible for incompatibility in a Japanese paternity case.

In a Japanese paternity test, an alleged father was excluded only by reverse homozygosity of esterase D (ESD) phenotypes (mother, ESD 1; child, ESD 1; alleged father, ESD 2) out of 43 classical and DNA markers investigated. To solve the aberrant inheritance of the ESD phenotypes observed between them, fragments for all eight coding exons amplified by polymerase chain reaction (PCR) were subjected to DNA analysis. The child and alleged father shared a null allele, originating from ESD(*)1. It was characterized by having TGA for the stop codon instead of TCA for serine at codon 63. Thus, the sharing of a rare null gene, ESD(*)Q0(yonago), increased the probability of paternity.

Alleles↗
PubMed2002

Extreme mtDNA homogeneity in continental Asian populations.

Mitochondrial DNA (mtDNA) variation in continental Asia has not been well-studied. Here, we report mtDNA HV1 sequences for 84 Xi'an and 82 Changsha Han Chinese, 89 Honshu Japanese, and 35 Vietnamese. Comparison of these sequences with other Asian mtDNA sequences reveals high variability within populations, but extremely low differentiation among Asian populations. Correlations between genetic distance and geographic distance, based on mtDNA and Y chromosome variation, indicate a higher migration rate in females than in males. This may reflect patrilocality, as suggested previously, but another plausible hypothesis is that the demographic expansion associated with the spread of agriculture in Asia may be responsible for the extreme genetic homogeneity in Asia.

Asia↗
PubMed2002

Complete mitochondrial DNA sequence of a tadpole shrimp (Triops cancriformis) and analysis of museum samples.

The complete mitochondrial DNA (mtNDA) of the tadpole shrimp Triops cancriformis was sequenced. The sequence consisted of 15,101 bp with an A+T content of 69%. Its gene arrangement was identical with those sequences of the water flea (Daphnia pulex) and giant tiger prawn (Penaeus monodon), whereas it differed from that of the brine shrimp (Artemia franciscana) in the arrangement of its genes for tRNAs. Phylogenetic analysis revealed T. cancriformis to be more closely related to the water flea than to the brine shrimp and giant tiger prawn. We also compared the 16S rRNA sequences of five formalin-fixed tadpole shrimps that had been collected in five different locations and stored in a museum. The sequence divergence was in the range of 0-1.51%, suggesting that those samples were closely related to each other.

Animals↗