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Yoichi Matsubara

Publications and source records attributed to Yoichi Matsubara.

At least 37 records · Page 2Linked to original sources
PubMed2004

Significant association between nonsyndromic oral clefts and arylhydrocarbon receptor nuclear translocator (ARNT).

The etiology of nonsyndromic oral clefts (cleft lip, cleft palate, or cleft lip and palate) is still controversial, but is considered to involve both genetic and environmental factors. One of suspected environmental factors is 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) found in tobacco, herbicides, contaminated soil, and food. TCDD administered during organogenesis in mice causes a high incidence of CP in fetuses. There is ample evidence that aryl hydrocarbon receptor (AHR), AHR nuclear translocator (ARNT), and cytochrome P450 1A1 (CYP1A1) are involved in TCDD metabolism. We assessed whether there is any association in the Japanese population of nonsyndromic oral clefts with single nucleotide polymorphisms (SNPs) in the AHR, ARNT, and CYP1A1 genes using transmission disequilibrium test (TDT) and case-control study. We identified and investigated three SNPs in ARNT; 567G/C (V189V), IVS12-19T/G, and 2117C/T (P706L). Two amino acid substitutions, R554L in AHR and I462V in CYP1A1, were also investigated. In the TDT, the C allele of ARNT 567G/C was preferentially transmitted to patients (P = 0.033). When a haplotype consisting of 567G/C and IVS12-19T/G in ARNT was considered, the preferential transmission of the CT (567C-IVS12-19T) haplotype was observed (P = 0.0012). In a case-control study, a significant association of IVS12-19T/G in ARNT was observed (P = 0.021). The SNPs studied in AHR and CYP1A1 were not associated with the disease. Our results suggest that ARNT is involved in the development of nonsyndromic oral clefts in the Japanese population.

Adult↗
PubMed2004

Association between nonsyndromic cleft lip with or without cleft palate and the glutamic acid decarboxylase 67 gene in the Japanese population.

Nonsyndromic cleft lip with or without cleft palate (NSCLP) is one of the most common craniofacial malformations. Both genetic and environmental factors are involved in the pathogenesis. In addition to its role as an inhibitory neurotransmitter, gamma-aminobutyric acid (GABA) synthesized by glutamic acid decarboxylase (GAD) is presumed to play a role in normal embryonic, especially facial, development. This notion has been substantiated by the fact that Gad67 knockout mice have been shown to have cleft palate. We hypothesized that GAD67 may be involved in the development of NSCLP and investigated the possible association between the GAD67 gene (GAD67) and NSCLP in Japanese patients. We screened 50 probands for single nucleotide polymorphisms (SNPs) in GAD67 using denaturing high performance liquid chromatography (DHPLC) and found seven SNPs. Since two SNPs showed complete linkage disequilibrium (LD) to the other SNPs, we constructed a 5-locus haplotype of GAD67. The frequency distribution of the haplotype differed between NSCLP patients and controls (P = 0.0028). The frequency of -445A, -292A, -147G, 111C, and IVS9-39T haplotype in the NSCLP patients was significantly lower than that in controls (P = 0.00098). In a transmission disequilibrium test (TDT) in 99 parent-offspring trios, we found -445C, -292C, -147G, 111C, and IVS9-39C haplotype was preferentially transmitted to the patients with cleft lip and palate (P = 0.0077). Our data suggest that GAD67 is involved in the pathogenesis of NSCLP in the Japanese population.

Asian People↗
PubMed2004

Linkage and association of childhood asthma with the chromosome 12 genes.

Several studies have shown linkage of chromosome region 12q13-24 to bronchial asthma and related phenotypes in ethnically diverse populations. In the Japanese population, a genome-wide study failed to show strong evidence of linkage of this region. Chromosome 12 genes that showed association with the disease in at least one report include: the signal transducer and activator of transcription 6 gene ( STAT6), the nitrogen oxide synthetase 1 gene ( NOS1), the interferon gamma gene ( IFNG), and the activation-induced cytidine deaminase gene ( AICDA). To evaluate the linkage between chromosome 12 and childhood asthma in the Japanese population, we performed sib-pair linkage analysis on childhood asthma families using 18 microsatellite markers on chromosome 12. To investigate association between chromosome 12 candidate genes and asthma, distributions of alleles and genotypes of repeat polymorphisms of STAT6, NOS1, and IFNG were compared between controls and patients. Single nucleotide polymorphism of AICDA was also investigated. Chromosome region 12q24.23-q24.33 showed suggestive linkage to asthma. The NOS1 intron 2 GT repeat and STAT6 exon 1 GT repeat were associated with asthma. Neither the IFNG intron 1 CA repeat nor 465C/T of AICDA showed any association with asthma. Our results suggest that NOS1 and STAT6 are asthma-susceptibility genes and that chromosome region 12q24.23-q24.33 contains other susceptibility gene(s).

Adolescent↗
PubMed2004

Collaboration of breast cancer clinic and genetic counseling division for BRCA1 and BRCA2 mutation family in Japan.

BACKGROUND: BRCA1 and BRCA2 mutations cause high breast cancer incidence rates as high as 80% Although prophylactic therapy is still controversial, several prophylactic therapies have been proposed and tried for BRCA1 and BRCA2 mutation carriers. Prophylactic surgery, chemo-prevention and precise screening have been proposed as prophylactic therapy. All BRCA1 and BRCA2 mutation carriers need knowledge about their disease and the countermeasures that are used to protect against onset of disease. Counseling plays an important role in this regard for people with genetic diseases. Therefore, collaboration between breast cancer clinics and genetic counseling services is the most important issue in clinical practice. Our group consists of three national universities and a general hospital. In this article we describe our trial to construct a clinical system against hereditary breast cancer as an interim report for the Japanese Ministry of Health, Labour and Welfare. PATIENTS AND METHODS: Twenty familial breast cancer patients were registered in this study. The whole sequence of BRCA1 and BRCA2 were analyzed. If pathological mutations were detected, their first degree families were introduced to the counseling division at each institute when candidates visited counseling divisions. RESULTS AND DISCUSSION: Four cases of a deleterious mutation in BRCA1 or BRCA2 were detected among 20 cases. Their first degree relatives are now under consideration for visiting counseling divisions. The clinical system described in this study should play a role to protect BRCA1 or BRCA2 mutation carriers in Japan.

Breast Neoplasms↗
PubMed2004

Variations in the C3, C3a receptor, and C5 genes affect susceptibility to bronchial asthma.

Bronchial asthma (BA) is a common chronic inflammatory disease characterized by hyperresponsive airways, excess mucus production, eosinophil activation, and the production of IgE. The complement system plays an immunoregulatory role at the interface of innate and acquired immunities. Recent studies have provided evidence that C3, C3a receptor, and C5 are linked to airway hyperresponsiveness. To determine whether genetic variations in the genes of the complement system affect susceptibility to BA, we screened single nucleotide polymorphisms (SNPs) in C3, C5, the C3a receptor gene (C3AR1), and the C5a receptor gene (C5R1) and performed association studies in the Japanese population. The results of this SNP case-control study suggested an association between 4896C/T in the C3 gene and atopic childhood BA (P = 0.0078) as well as adult BA (P = 0.010). When patient data were stratified according to elevated total IgE levels, 4896C/T was more closely associated with adult BA (P = 0.0016). A patient-only association study suggested that severity of childhood BA was associated with 1526G/A of the C3AR1 gene (P = 0.0057). We identified a high-risk haplotype of the C3 gene for childhood (P = 0.0021) and adult BA (P = 0.0058) and a low-risk haplotype for adult BA (P = 0.00011). We also identified a haplotype of the C5 gene that was protective against childhood BA (P = 1.4 x 10(-6)) and adult BA (P = 0.00063). These results suggest that the C3 and C5 pathways of the complement system play important roles in the pathogenesis of BA and that polymorphisms of these genes affect susceptibility to BA.

Adult↗
PubMed2004

Mild variant of nonketotic hyperglycinemia with typical neonatal presentations: mutational and in vitro expression analyses in two patients.

In neonatal-onset nonketotic hyperglycinemia, severe psychomotor retardation is the expected uniform outcome. We report two patients with typical neonatal presentation who showed far better developmental outcomes. The in vitro expression analysis of the identified GLDC mutations revealed considerable residual enzyme activity, suggesting prognostic and enzymatic heterogeneity even in neonatal-onset nonketotic hyperglycinemia.

Amino Acid Oxidoreductases↗
PubMed2004

Genetic testing of glycogen storage disease type Ib in Japan: five novel G6PT1 mutations and a rapid detection method for a prevalent mutation W118R.

We devised a simple method using a TaqMan fluorogenic probe for detection of a prevalent G6PT1 mutation W118R among Japanese patients with glycogen storage disease type Ib. The W118R mutation was detected in three of six newly diagnosed Japanese patients. The W118R-negative alleles were screened for causative mutations by sequencing analysis, revealing five novel mutations. The genetic tests using the simple TaqMan method coupled with sequencing analysis would facilitate the early diagnosis of this disorder.

Adult↗
PubMed2004

Mutation spectrum of the PCCA and PCCB genes in Japanese patients with propionic acidemia.

Propionic acidemia (PA) is an inborn error of organic acid metabolism caused by a deficiency of propionyl-CoA carboxylase. This enzyme is composed of two non-identical subunits, alpha and beta, which are encoded by the PCCA and PCCB genes, respectively. An enzyme deficiency can result from mutations in either PCCA or PCCB. To elucidate the mutation spectrum in Japanese patients, we have performed a mutation analysis of 30 patients with PA, which included nine previously reported patients. The study revealed that 15 patients were alpha-subunit deficient and 15 patients were beta-subunit deficient. Seven novel mutations were found (IVS18-6C >G, 1746G >A, C398R, G197E and IVS18+1G >A in the PCCA; A153P and IVS9+1G >T in the PCCB). Among these Japanese patients with alpha-subunit deficiencies, 923-924insT, IVS18-6C >G, and R399Q mutations were frequent and the total allelic frequency of these three mutations combined was 56% (17/30). This is in sharp contrast to the mutation spectrum found in Caucasian patients, where no prevalent mutations have been identified. Among the beta-subunit deficiencies, there were three frequent mutations; R410W, T428I, and A153P, whose allelic frequencies were 30, 26.7, and 13.3%, respectively. In conclusion, a limited number of mutations are predominant in both PCCA and PCCB genes among Japanese patients with propionic acidemia.

Amino Acid Metabolism, Inborn Errors↗
PubMed2004

Mutation analysis of the MMAA and MMAB genes in Japanese patients with vitamin B(12)-responsive methylmalonic acidemia: identification of a prevalent MMAA mutation.

Methylmalonic acidemia (MMA) is caused by the deficient activity of l-methylmalonyl-CoA mutase, which is a vitamin B(12) (or cobalamin, Cbl)-dependent enzyme. MMA due to the effect of insufficient Cbl metabolism is classified into three forms (cblA, cblB, and cblH). Recently, the genes responsible for cblA and cblB were identified as MMAA and MMAB, respectively. The MMAA protein likely transports Cbl into the mitochondria for adenosylcobalamin synthesis, while the MMAB protein appears to be an adenosyltransferase. We performed a mutation analysis of 10 unrelated Japanese patients with vitamin B(12)-responsive MMA. Seven patients had mutations in MMAA, whereas the other three patients showed no disease-causing substitutions in either MMAA or MMAB. Five novel mutations were identified in MMAA (R22X, R145X, L217X, R359G, and 503delC). The 503delC mutation was observed in five of the seven MMAA patients, suggesting that the mutation is prevalent in Japanese patients. This finding may facilitate the DNA diagnosis of vitamin B(12)-responsive MMA within the Japanese population.

Acidosis↗
PubMed2004

Mutation detection of GJB2 using IsoCode and real-time quantitative polymerase chain reaction with SYBR green I dye for newborn hearing screening.

OBJECTIVES/HYPOTHESIS: Recent developments in molecular genetics have opened a new era in genetic analysis accompanied by new concepts concerning genetic disorders. Although 30 genes responsible for nonsyndromic deafness have been discovered as of March 27, 2003, the connexin 26 gene (GJB2) is commonly found in cases of deafness of unknown origins. The GJB2 contains a predicted open reading frame of 785 base pairs, which makes it relatively easy to detect mutations. Accordingly, mutation analysis of GJB2 should be suitable for the screening of congenital deafness. STUDY DESIGN: Prospective study. METHODS: IsoCode Stix is a useful device to isolate DNA from small samples of blood, which can be delivered from remote areas. To apply the detection of common mutations of GJB2 to hearing screening, DNA was extracted from several droplets of blood applied to the IsoCode device, and an allele-specific amplification method with real-time quantitative polymerase chain reaction was performed using GeneAmp 7700 with SYBR Green I dye. RESULTS: DNA extracted from IsoCode was purified within 45 minutes, which was sufficient to detect the full sequence of GJB2. Four types of common GJB2 mutations were reliably detected within 2.5 hours. CONCLUSION: IsoCode and real-time quantitative polymerase chain reaction will be promising tools for newborn screening of deafness genes in the future in DNA-based deafness screening, allowing early diagnosis of deafness and prompt training for language development.

Benzothiazoles↗
PubMed2004

Glycine cleavage system in neurogenic regions.

The glycine cleavage system (GCS) is the essential enzyme complex for degrading glycine and supplying 5,10-methylenetetrahydrofolate for DNA synthesis. Inherited deficiency of this system causes nonketotic hyperglycinemia, characterized by severe neurological symptoms and frequent association of brain malformations. Although high levels of glycine have been considered to cause the above-mentioned problems, the detailed pathogenesis of this disease is still unknown. Here we show that GCS is abundantly expressed in rat embryonic neural stem/progenitor cells in the neuroepithelium, and this expression is transmitted to the radial glia-astrocyte lineage, with prominence in postnatal neurogenic regions. These data indicate that GCS plays important roles in neurogenesis, and suggest that disturbance of neurogenesis induced by deficiency of GCS may be the main pathogenesis of nonketotic hyperglycinemia.

Amino Acid Oxidoreductases↗
PubMed2004

Genotyping of single nucleotide polymorphisms (SNPs) influencing drug response by competitive allele-specific short oligonucleotide hybridization (CASSOH) with immunochromatographic strip.

Using competitive allele-specific oligonucleotide hybridization with immunochromatographic strip (CASSOH), we have developed a simplified method for the detection of eight polymorphisms that are especially important in the identification of drug responders or non-responders and patients at increased risk of drug toxicity. The genotyping method is unambiguously determined by the presence or the absence of visible purple lines on the immunochromatographic strip, and results are obtained within 5 min after PCR. This method is rapid, highly sensitive, simplified, and should be suitable for point-of-care genotyping in clinical settings.

Alleles↗
PubMed2003

Long-term treatment and diagnosis of tetrahydrobiopterin-responsive hyperphenylalaninemia with a mutant phenylalanine hydroxylase gene.

A novel therapeutic strategy for phenylketonuria (PKU) has been initiated in Japan. A total of 12 patients who met the criteria for tetrahydrobiopterin (BH(4))-responsive hyperphenylalaninemia (HPA) with a mutant phenylalanine hydroxylase (PAH) (EC 1.14.16.1) gene were recruited at 12 medical centers in Japan between June 1995 and July 2001. Therapeutic efficacy of BH(4) was evaluated in single-dose, four-dose, and 1-wk BH(4) loading tests followed by long-term BH(4) treatment, and also examined in relation to the PAH gene mutations. The endpoints were determined as the percentage decline in serum phenylalanine from initial values after single-dose (>20%), four-dose (>30%), and 1-wk BH(4) (>50%) loading tests. Patients with mild PKU exhibiting decreases in blood phenylalanine concentrations of >20% in the single-dose test also demonstrated decreases of >30% in the four-dose test. The 1-wk test elicited BH(4) responsiveness even in patients with poor responses in the shorter tests. Patients with mild HPA, many of whom carry the R241C allele, responded to BH(4) administration. No clear correlation was noted between the degree of decrease in serum phenylalanine concentrations in the single- or four-dose tests and specific PAH mutations. The 1-wk test (20 mg/kg of BH(4) per day) is the most sensitive test for the diagnosis of BH(4)-responsive PAH deficiency. Responsiveness apparently depends on mutations in the PAH gene causing mild PKU, such as R241C. BH(4) proved to be an effective therapy that may be able to replace or liberalize the phenylalanine-restricted diets for a considerable number of patients with mild PKU.

Biopterins↗
PubMed2003

Novel IRF6 mutations in Japanese patients with Van der Woude syndrome: two missense mutations (R45Q and P396S) and a 17-kb deletion.

Three Japanese families with Van der Woude syndrome (VWS) were screened for mutations in the interferon regulatory factor 6 gene (IRF6) by sequencing its entire coding region. Two novel missense mutations, R45Q in exon 3 and P396S in exon 9, were identified in families 1 and 2, respectively. In family 3, no causative base change was found by the sequencing analysis, but a deletion involving exons 4-9 was suggested by multiplex PCR analysis. To confirm the deletion and to determine its 5'- and 3'-boundaries, we amplified a DNA fragment containing a heterozygous polymorphic site in exon 2 by using a 5'-upstream forward PCR primer and eight different reverse primers located 3'-downstream of exon 2. The amplified product was subjected to nested PCR to generate a DNA fragment containing the polymorphic site. When a reverse primer located within the deletion was used for the first PCR amplification, only the nondeletion allele was detected after the second PCR. Repeated analyses with eight different reverse primers allowed us to map the boundaries of the deletion, and subsequently a heterozygous 17,162-bp deletion involving exons 4-9 was identified. Since IRF6 mutations in a significant portion of VWS patients remain undetected by conventional sequencing analysis, it may be important to search for a large deletion in those patients. Our simple methods to identify deletions and to determine the boundaries of a deletion would facilitate the identification of such patients.

Cleft Lip↗
PubMed2003

Transgenic expression of a dominant-negative connexin26 causes degeneration of the organ of Corti and non-syndromic deafness.

Hereditary deafness affects about 1 in 2000 children and mutations in the GJB2 gene are the major cause in various ethnic groups. GJB2 encodes connexin26, a putative channel component in cochlear gap junction. However, the pathogenesis of hearing loss caused by the GJB2 mutations remains obscure. The generation of a mouse model to study the function of connexin26 during hearing has been hampered by the fact that Gjb2 knockout mice are embryonic lethal. To establish viable model mice we generated transgenic mice expressing a mutant connexin26 with R75W mutation that was identified in a deaf family with autosomal-dominant inheritance. The previous expression analysis revealed that the R75W connexin26 inhibited the gap channel function of the co-expressed normal connexin26 in a dominant-negative fashion. We established two lines of transgenic mice that showed severe to profound hearing loss, deformity of supporting cells, failure in the formation of the tunnel of Corti and degeneration of sensory hair cells. Despite robust expression of the transgene, no obvious structural change was observed in the stria vascularis or spiral ligament that is rich in connexin26 and generates the endolymph. The high resting potential in cochlear endolymph essential for hair cell excitation was normally sustained. These results suggest that the GJB2 mutation disturbs homeostasis of cortilymph, an extracellular space surrounding the sensory hair cells, due to impaired K(+) transport by supporting cells, resulting in degradation of the organ of Corti, rather than affecting endolymph homeostasis in mice and probably in humans.

Amino Acid Substitution↗
PubMed2003

Detection of single nucleotide substitution by competitive allele-specific short oligonucleotide hybridization (CASSOH) with immunochromatographic strip.

Recent advances in human genome research have revealed that genetic polymorphisms, such as single nucleotide polymorphisms (SNPs), are closely associated with susceptibility to various common diseases and adverse drug reactions. Also, numerous mutations responsible for a number of genetic diseases have been identified. Clinical application of genetic information to individual health care requires simple and rapid identification of nucleotide changes in clinical settings. We have devised a novel low-tech method for the detection of a single nucleotide substitution using competitive allele-specific short oligonucleotide hybridization with immunochromatographic strip. The gene of interest is PCR-amplified, hybridized to an allele-specific short oligonucleotide probe in the presence of a competitive oligonucleotide, and subjected to chromatography using a DNA test strip at room temperature. The genotype is unambiguously determined by the presence or the absence of visible purple lines on a strip. Feasibility of the method was demonstrated by the detection of a prevalent disease-causing mutations in glycogen storage disease type Ia (G6PC), medium-chain acyl-CoA dehydrogenase deficiency (ACADM), non-ketotic hyperglycinemia (GLDC), and clinically important polymorphisms in the CYP2C19 gene and the aldehyde dehydrogenase 2 gene (ALDH2). The procedure does not demand either technical expertise or expensive instruments and is readily performed in local clinical laboratories. The result is obtained within 10 min after PCR. This rapid and simple method of SNP detection may be used for point-of-care genetic diagnosis with potentially diverse clinical applications. Hum Mutat 22:166-172, 2003.

Alleles↗
PubMed2003

A missense mutation in the SH3BP2 gene on chromosome 4p16.3 found in a case of nonfamilial cherubism.

OBJECTIVE: Cherubism is a rare hereditary multilocular cystic disease of the jaws, characterized by its typical appearance. Although nonfamilial cases have been reported, it is difficult to distinguish nonfamilial cherubism from central giant cell granuloma. Recent studies have revealed the point mutations in the SH3BP2 gene on chromosome 4p16.3 in cherubism families. In this article, the SH3BP2 gene in nonfamilial cherubism was examined. PATIENT: A 21-year-old Japanese woman with nonfamilial cherubism. INTERVENTIONS: Genomic DNA was purified from a blood sample obtained from the patient and used for direct sequencing. In addition, a sample of the lesion, resected during surgery, was used for histologic and immunohistochemical purposes. RESULTS: Genomic DNA sequencing found a Pro418Arg mutation in the SH3BP2 gene of the patient. In a histochemical analysis, the multinucleated giant cells proved to be strongly positive for PGM-1, KP-1, and tartrate-resistant acid phosphatase and faintly positive for osteopontin. CONCLUSIONS: The missense mutation Pro418Arg was identified in the SH3BP2 gene from a nonfamilial case of cherubism. DNA diagnosis may play a significant role in the identification of cherubism.

Acid Phosphatase↗