Teruaki Tozaki

Laboratory of Racing Chemistry, Tochigi, Tochigi-ken, Japan

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Publications (30)71.34 Total impact

  • Article: Thyroid Profiles in a Patient with Resistance to Thyroid Hormone and Episodes of Thyrotoxicosis, including Repeated Painless Thyroiditis.
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    ABSTRACT: Background: Thyrotoxic disease can be difficult to recognize in patients with resistance to thyroid hormone because the clinical symptoms of thyrotoxicosis cannot be observed, and thyrotropin (TSH) may not be suppressed because of hormone resistance. Painless thyroiditis is a relatively common cause of thyrotoxicosis, but its occurrence in resistance to thyroid hormone has not been reported. We assessed the thyroid profile in a patient with resistance to thyroid hormone and episodes of thyrotoxicosis who experienced repeated painless thyroiditis. Patient Findings: A 44-year-old Japanese woman with resistance to thyroid hormone, which was confirmed by the P453A mutation in the thyroid hormone receptor ß (TRß) gene, showed a slight elevation of the basal levels of thyroid hormones, which indicated that her pituitary resistance to thyroid hormone was mild. She experienced a slight exacerbation of hyperthyroxinemia concomitant with TSH suppression. A diagnosis of painless thyroiditis was made because of the absence of TSH receptor antibodies, low Tc-99m pertechnetate uptake by the thyroid gland and a transient, slight elevation of TSH following the elevation of thyroid hormones. The patient's complaints of general malaise and occasional palpitations did not change throughout the course of painless thyroiditis. Three years later, painless thyroiditis occurred again without any deterioration of the clinical manifestations. Conclusions: Mild pituitary resistance to thyroid hormone can be overcome by slight exacerbation of hyperthyroxinemia during mild thyrotoxicosis. When pituitary resistance is severe and TSH is not suppressed, thyrotoxicosis may be overlooked.
    Thyroid: official journal of the American Thyroid Association 12/2012; · 2.60 Impact Factor
  • Article: Individual Identification of Racehorses from Urine Samples Using a 26-Plex Single-Nucleotide Polymorphism Assay.
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    ABSTRACT: To construct a system for identifying individual horses from urine samples that are submitted for postracing doping tests, we developed a genotyping assay based on 26-plex single-nucleotide polymorphisms (SNPs). DNA was isolated from urine using a commercially available DNA/RNA extraction kit, and SNP genotyping was achieved with a SNaPshot(™) technique. DNA profiles including 26 SNPs were acquired from urine samples and blood/hair samples. Within the studied Thoroughbred population, the 26-plex assay showed a probability of identity of 5.80 × 10(-11) . Compared to the conventional short tandem repeat assay, the SNP assay used less DNA, and the rate of successful genotyping was improved to 97% using aliquots of horse urine as small as 140 μL. The urinary DNA could be successfully genotyped under proper storage concerning refrigeration or freeze-thawing. This SNP assay can be used for individual identification when suspicious results are obtained from horse doping tests.
    Journal of Forensic Sciences 10/2012; · 1.23 Impact Factor
  • Article: A Case of Ambiguous External Genitalia in a Thoroughbred Male Horse with 63,XO/64,XY Mosaic Karyotype.
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    ABSTRACT: A Thoroughbred colt with ambiguous external genitalia was presented for clinical and histological examinations. The colt had a short penis, located between his hind limbs and faced backward. The measurements of luteinizing hormone, follicle stimulating hormone, testosterone and ir-inhibin showed a tendency to increase gradually from April. Both sex-determining region of the Y chromosome and amelogenin gene fragments were detected by PCR method. The cytogenetic analysis revealed the 63,XO/64,XY mosaic karyotype (ratio 83:17). In autopsy, immature symmetrical subcutaneous testes were found in the inguinal regions. The testes and the other accessory sex organs were histologically normal. These results add to our knowledge of chromosomal abnormality and information of disorders of sex development in horse.
    Journal of Veterinary Medical Science 05/2012; · 0.85 Impact Factor
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    Article: Multiple SNPs in intron 41 of thyroglobulin gene are associated with autoimmune thyroid disease in the Japanese population.
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    ABSTRACT: BACKGROUND: The etiology of the autoimmune thyroid diseases (AITDs), Graves' disease (GD) and Hashimoto's thyroiditis (HT), is largely unknown. However, genetic susceptibility is believed to play a major role. Two whole genome scans from Japan and from the US identified a locus on chromosome 8q24 that showed evidence for linkage with AITD and HT. Recent studies have demonstrated an association between thyroglobulin (Tg) polymorphisms and AITD in Caucasians, suggesting that Tg is a susceptibility gene on 8q24. OBJECTIVES: The objective of the study was to refine Tg association with AITD, by analyzing a panel of 25 SNPs across an extended 260 kb region of the Tg. METHODS: We studied 458 Japanese AITD patients (287 GD and 171 HT patients) and 221 matched Japanese control subjects in association studies. Case-control association studies were performed using 25 Tg single nucleotide polymorphisms (SNPs) chosen from a database of the Single Nucleotide Polymorphism Database (dbSNP). Haplotype analysis was undertaken using the computer program SNPAlyze version 7.0. PRINCIPAL FINDINGS AND CONCLUSIONS: In total, 5 SNPs revealed association with GD (P<0.05), with the strongest SNP associations at rs2256366 (P = 0.002) and rs2687836 (P = 0.0077), both located in intron 41 of the Tg gene. Because of the strong LD between these two strongest associated variants, we performed the haplotype analysis, and identified a major protective haplotype for GD (P = 0.001). These results suggested that the Tg gene is involved in susceptibility for GD and AITD in the Japanese.
    PLoS ONE 01/2012; 7(5):e37501. · 4.09 Impact Factor
  • Article: Genetic characterization of the endangered Kiso horse using 31 microsatellite DNAs.
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    ABSTRACT: In order to contribute to conservation of the endangered Kiso horse, we clarified their genetic information using 31 microsatellite DNAs, and genotyped 125 horses, 83% of the existing breed. First, we clarified the current status of the horses. The horses were confirmed to have experienced rapid loss of population causing a bottleneck, and their effective population size was much smaller than their census size. Moreover, the number of alleles (6.3), observed heterozygosity (0.674), and expected heterozygosity (0.662) were in the same range as other endangered horses all over the world. Therefore, although their inbreeding level was not so severe (F(is): -0.017), the Kiso horse is surely one of the endangered. Second, we obtained genetic information of individuals. This information allowed us to understand the genetic distance of individuals, and might help in development of a reproductive strategy concerning the genetic distance between the mating pairs. Moreover, there appeared to be 4 subpopulations of Kiso horse, and this result was in good agreement with their historical background. Third, we confirmed that the parentage test for identification using the 31 microsatellite DNAs was highly reliable (probability of exclusion: 0.999999993). This identification increases the reliability of stud certification, and is also helpful for effective management. Understanding the genetic diversity within the population and the relationships among individuals is important to ensuring effective management for maintenance of genetic variation, and this study may help in conservation of the endangered Kiso horse.
    Journal of Veterinary Medical Science 09/2011; 74(2):161-6. · 0.85 Impact Factor
  • Article: Sequence variants at the myostatin gene locus influence the body composition of Thoroughbred horses.
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    ABSTRACT: Myostatin is a member of the transforming growth factor-β family with a key role in inhibition of muscle growth by negative regulation of both myoblast proliferation and differentiation. Recently, a genomic region on ECA18, which includes the MSTN gene, was identified as a candidate region influencing racing performance in Thoroughbreds. In this study, four SNPs on ECA18, g.65809482T>C, g.65868604G>T, g.66493737C>T, and g.66539967A>G, were genotyped in 91 Thoroughbred horses-in-training to evaluate the association between genotype and body composition traits, including body weight, withers height, chest circumference, cannon circumference, and body weight/withers height. Of these, statistically differences in body weight and body weight/withers height were associated with specific genotypes in males. Specifically, body weight/withers height showed statistically significant differences depending on genotype at g.658604G>T, g.66493737C>T, and g.66539967A>G (P<0.01) in males during the training period. Animals with a genotype associated with suitability for short-distance racing, C/C at g.66493737C>T, had the highest value (3.17 ± 0.05 kg·cm(-1)) for body weight/withers height in March, while those with a genotype associated with suitability for long-distance racing, T/T, had the lowest (2.99 ± 0.03 kg·cm(-1)). In females, the trends in the association of body weight/withers height with genotypes were similar to those observed in males. As the SNPs are not believed to be linked to coding variants in MSTN, these results suggest that regulation of MSTN gene expression influences skeletal muscle mass and hence racing performance, particularly optimum race distance, in Thoroughbred horses.
    Journal of Veterinary Medical Science 08/2011; 73(12):1617-24. · 0.85 Impact Factor
  • Article: Association of the protein tyrosine phosphatase nonreceptor 22 haplotypes with autoimmune thyroid disease in the Japanese population.
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    ABSTRACT: A missence single-nucleotide polymorphism (SNP) in the protein tyrosine phosphatase nonreceptor 22 (PTPN22) gene known as R620W (rs2476601) was recently reported to be associated with several autoimmune diseases including Graves' disease (GD). The association was repeatedly confirmed in the populations of North European ancestry. However, this amino acid was reported to be nonpolymorphic in the Asian populations. Since the gene confers an impact on autoimmune diseases, we attempt to explore an association between the PTPN22 gene and autoimmune thyroid disease (AITD) in a Japanese population without restricting to rs2476601. Previous investigations have also demonstrated that two intronic SNPs (rs706778 and rs3118470) in the interleukin-2 receptor-alpha (IL2RA) gene were associated with type 1 diabetes in the Japanese population. We genotyped the five SNPs (rs12760457, rs2797415, rs1310182, rs2476599, and rs3789604) of the PTPN22 and the two SNPs (rs706778 and rs3118470 in the IL2RA gene) in 456 Japanese patients with AITD (286 with GD, 170 with Hashimoto's thyroiditis) and 221 matched Japanese control subjects. Seven SNPs were analyzed by either the SNAPshot method or the high-resolution melting and unlabeled probe methods. Case-control association studies were performed using the chi(2) and Fisher's exact tests with Yates correction. Haplotype was conducted using the expectation-maximization algorithm. No association was found between any of the individual SNPs of the PTPN22 gene and AITD. Permutation analysis revealed that the distribution of one haplotype is significantly different between patients with AITD and controls (p = 0.0036). A novel protective effect of a haplotype containing five SNPs was observed (p < 0.0001 for AITD, p < 0.0001 for GD, and p < 0.0001 for Hashimoto's thyroiditis, respectively). The GG allele of rs3118470 in the IL2RA gene was significantly associated with GD (p = 0.03), although the association was weak. Significant difference in the distribution of the haplotype suggests that the PTPN22 gene rather than rs2476601 is involved in the development of AITD in the Japanese population.
    Thyroid: official journal of the American Thyroid Association 08/2010; 20(8):893-9. · 2.60 Impact Factor
  • Article: Association of PTPN22 haplotypes with type 1 diabetes in the Japanese population.
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    ABSTRACT: The R620W polymorphism in the protein-tyrosine-phosphatase nonreceptor type 22 gene (PTPN22) confers susceptibility to type 1 diabetes (T1D) and other autoimmune diseases. This polymorphism is reportedly nonpolymorphic in the Asian population. Additional polymorphisms and specific haplotypes have also been associated with T1D, rheumatoid arthritis (RA) and Graves' disease in Caucasians. We examined whether PTPN22 single nucleotide polymorphisms (SNPs) other than R620W and haplotypes are associated with T1D in the Japanese population. We compared the allele frequencies of five haplotype-tagging SNPs in the PTPN22 gene, 2 of which are reportedly associated with RA in Caucasians (rs3789604 and rs1310182), and compared haplotype distributions between 184 Japanese T1D patients and 179 healthy controls. rs3789604 was not associated with T1D in our Japanese subjects. The frequency of the C allele of rs1310182 differed significantly between T1D patients and controls. Permutation analysis revealed the distribution of this haplotype to differ significantly between T1D patients and controls. One rare haplotype that included the susceptibility allele of rs1310182 was more frequent, while another rare haplotype that included the protective allele of rs1310182 was absent, in T1D patients. This significant haplotype distribution difference suggests that polymorphisms in the PTPN22 gene other than R620W are involved in either predisposition to or protection from T1D in the Japanese population.
    Human immunology 08/2010; 71(8):795-8. · 2.55 Impact Factor
  • Article: Construction and validation of parentage testing for thoroughbred horses by 53 single nucleotide polymorphisms.
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    ABSTRACT: We characterized the SNP 53 JPN System for parentage verification during horse registry. The SNP 53 JPN System was constructed using 53 highly polymorphic single nucleotide polymorphisms (SNPs), which were amplified and genotyped with 2 multiplex assays. The SNP 53 JPN System showed good resolution for 95 unrelated thoroughbreds, and the exclusion probability (PE01) for each SNP ranged from 11.5 to 23.0%, resulting in a total PE01 value of 99.996%. These results indicate that the SNP 53 JPN System is useful for parentage testing of thoroughbreds. Of the 53 SNPs, 8 SNPs could be used to exclude a pseudo parent and sib combination found using the 2006 International Society for Animal Genetics (ISAG) horse comparison test, as efficiently as the parentage testing systems using short tandem repeats (STRs). Thus, we concluded that the SNP 53 JPN System could provide sufficient and reliable information for routine parentage testing of thoroughbred.
    Journal of Veterinary Medical Science 06/2010; 72(6):719-26. · 0.85 Impact Factor
  • Article: Association studies of the IL-23R gene in autoimmune thyroid disease in the Japanese population.
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    ABSTRACT: Autoimmune thyroid diseases (AITDs), including Graves' disease (GD) and Hashimoto's thyroiditis (HT), are caused by interplays of genetic factors and environmental triggers. Interleukin-23 and its receptor (IL-23R) guide T cells towards the Th17 phenotype. IL-23R single nucleotide polymorphisms (SNPs) have been shown to be associated with several autoimmune diseases, including Crohn's disease and rheumatoid arthritis, and Graves' ophthalmopathy (GO) in Caucasians. To determine whether variants in the IL-23R gene are associated with AITDs in Japanese, 464 Japanese AITD patients (290 with GD, 174 with HT) and 179 matched Japanese control subjects were genotyped for four SNPs spanning the IL-23R gene. SNPs rs11209026 and rs7530511 were genotyped using TaqMan allelic discrimination assays and SNPs rs2201841 and rs10889677 were genotyped using a fluorescent-based restriction fragment length polymorphism method. Case-control association studies were performed using the chi(2) and Fisher's exact tests with Yates correction. Of the four SNPs rs11209026 was non-polymorphic in our dataset. The other three SNPs were not associated with GD or GO or HT in our Japanese population. These results suggest that the IL-23R gene is associated with AITDs only in a specific ethnic group.
    Autoimmunity 12/2008; 42(2):126-30. · 2.47 Impact Factor
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    Article: Cytotoxic T-lymphocyte associated antigen 4 gene polymorphisms and autoimmune thyroid disease: a meta-analysis.
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    ABSTRACT: Cytotoxic T-lymphocyte associated antigen 4 (CTLA-4) polymorphisms have been widely examined for their associations with autoimmune thyroid diseases [Graves' disease (GD) and Hashimoto thyroiditis (HT)], but their relative population effect remains unclear. The aim was to generate large-scale evidence on whether the CTLA-4 polymorphisms (A49G and CT60) and haplotypes thereof increase the susceptibility to GD and/or HT. Meta-analyses of group-level data were reviewed from 32 (11,019 subjects) and 12 (4,479) published and unpublished studies for the association of the A49G polymorphism with GD and HT, respectively (PubMed and HuGeNet search until July 2006). There were 15 (n = 7246) and six (n = 3086) studies available for the CT60 polymorphism, respectively. Meta-analyses of individual-level data from 10 (4906 subjects) and five (2386) collaborating teams for GD and HT, respectively, were also reviewed. Association of gene variants and haplotypes with GD and HT was measured. Group-level data suggested significant associations with GD and HT for both A49G [odds ratios 1.49 (P = 6 x 10(-14)) and 1.29 (P = 0.001) per G allele, respectively] and CT60 [1.45 (P = 2 x 10(-9)) and 1.64 (P = 0.003) per G allele, respectively]. Results were consistent between Asian and Caucasian descent subjects. Individual-level data showed that compared with the AA haplotype, the risk conferred by the GG haplotype was 1.49 (95% confidence interval 1.31,1.70) and 1.36 (95% confidence interval 1.16,1.59) for GD and HT, respectively. Data were consistent with a dose-response effect for the G allele of CT60. The CT60 polymorphism of CTLA-4 maps an important genetic determinant for the risk of both GD and HT across diverse populations.
    Journal of Clinical Endocrinology &amp Metabolism 09/2007; 92(8):3162-70. · 6.50 Impact Factor
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    Article: The regulatory T cell gene FOXP3 and genetic susceptibility to thyroid autoimmunity: an association analysis in Caucasian and Japanese cohorts.
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    ABSTRACT: FOXP3 is a key gene in the development of regulatory T cells (Treg). FOXP3 expression commits naïve T cells to become Treg cells. Indeed, mutations in the FOXP3 gene cause severe systemic autoimmune diseases in humans and in mice. Therefore, we hypothesized that the FOXP3 gene may be associated with thyroid autoimmunity which is among the typical autoimmune diseases that develop in individuals with FOXP3 mutations. Moreover, the FOXP3 gene is located within an X-chromosome locus (Xp11.23) previously shown to be linked with autoimmune thyroid diseases (AITD). We tested the FOXP3 gene locus for association with AITD in two large cohorts of US Caucasians and Japanese AITD patients. We analyzed 269 Caucasian AITD patients (52 males and 217 females) and 357 Caucasian controls (159 males and 198 females), as well as 377 female Japanese AITD patients and 179 female Japanese controls. The FOXP3 gene locus was analyzed using four microsatellite polymorphisms [(GT)n; (TC)n; DXS573; DXS1208] flanking the FOXP3 gene locus. Interestingly, while no association was found between FOXP3 polymorphisms and AITD in the Japanese cohort there was a significant association in the Caucasian cohort. There was a significant association of the (TC)n polymorphism with AITD in the Caucasian male AITD patients (p=0.011; 5 degrees of freedom [df]). Similarly, there was an association between the DXS573 microsatellite and AITD in the Caucasian female AITD patients (p=0.00023; 4 df). These results suggest that polymorphisms of the FOXP3 gene may play a role in the genetic susceptibility to AITD in Caucasians, perhaps by altering FOXP3 function and/or expression.
    Journal of Autoimmunity 07/2007; 28(4):201-7. · 7.37 Impact Factor
  • Article: Whole-genome linkage disequilibrium screening for complex traits in horses.
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    ABSTRACT: The identification of candidate genes for significant traits is crucial. In this study, we developed and tested effective and systematic methods based on linkage disequilibrium (LD) for the identification of candidate regions for genes with Mendelian inheritance and those associated with complex traits. Our approach entailed the combination of primary screening using pooled DNA samples based on DeltaTAC, secondary screening using an individual typing method and tertiary screening using a permutation test based on the differences in the haplotype frequency between two neighbouring microsatellites. This series of methods was evaluated using horse coat colour traits (chestnut/non-chestnut) as a simple Mendelian inheritance model. In addition, the methods were evaluated using a complex trait model constructed by mixing samples from chestnut and non-chestnut horses. Using both models, the methods could detect the expected regions for the horse coat colour trait. The results revealed that LD extends up to several centimorgans in horses, indicating that whole-genome LD screening in horses could be performed systematically and efficiently by combining the above-mentioned methods. Since genetic maps based on microsatellites have been constructed for many other species, the approaches present here could have wide applicability.
    Molecular and General Genetics 07/2007; 277(6):663-72. · 2.63 Impact Factor
  • Article: Improved resolution of the comparative horse-human map: investigating markers with in silico and linkage mapping approaches.
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    ABSTRACT: Genetic maps are extremely important tools for tracing the genes that govern economically significant traits, and microsatellites are a significant component of these. In this study, we isolated 2346 novel horse microsatellites as resources for the construction of high-density horse genetic maps. Of these 2346 markers, 339 (14.5%) horse sequences showed sequence homology to DNA sequences in the human genome, demonstrating that microsatellites as type II markers are valuable resources for developing linkage maps and that they have a potential equal to that of type I markers for developing comparative maps. Of the 339 markers, 206 (60.8%) were assigned to horse chromosomes using the Animal Health Trust (AHT) full-sib reference family, and 195 (94.6%) of these localized to the expected syntenic locations on the human genome. These results confirmed the high level of accuracy of in silico mapping. Thus, the 339 markers that exhibited homology to the human genome increased the density of markers on the horse-human comparative map. The resulting comparative map will facilitate the use of horse microsatellites as genetic markers for the identification of quantitative trait loci (QTL) that have been mapped on the human genome. In addition, although the in silico and linkage mapping data did not agree for the other 11 (5.4%) of the assigned 206 markers, these may represent new putative regions of horse-human synteny.
    Gene 06/2007; 392(1-2):181-6. · 2.34 Impact Factor
  • Article: Molecular analysis using mitochondrial DNA and microsatellites to infer the formation process of Japanese native horse populations.
    Hironaga Kakoi, Teruaki Tozaki, Hitoshi Gawahara
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    ABSTRACT: To assess the genetic diversity of Japanese native horse populations, we examined seven such populations using mitochondrial DNA (mtDNA) and microsatellite analyses. Four reference populations of Mongolian horses and European breeds were employed as other equids. In the mtDNA analysis, the control region (D-loop) of 411 bp was sequenced, and 12 haplotypes with 33 variable sites were identified in the Japanese native horses. The phylogenetic tree constructed by haplogrouping and using worldwide geographic references indicated that the haplotypes of the Japanese native horses were derived from six equid clusters. Compared with the foreign populations, the Japanese native populations showed lower within-population diversity and higher between-population differentiation. Microsatellite analysis, using 27 markers, found an average number of alleles per locus of 9.6 in 318 native and foreign horses. In most native populations, the within-population diversity was lower than that observed in foreign populations. The genetic distance matrix based on allelic frequency indicated that several native populations had notably high between-population differentiation. The molecular co-ancestry-based genetic distance matrix revealed that the European populations were differentiated from the Japanese and Mongolian populations, and no clear groups could be identified among the Japanese native horse populations. The genetic distance matrices had few correlations with the geographic distribution of the Japanese native populations. Based on the results of both mtDNA and microsatellite analyses, it could be speculated that each native population was formed by the founder populations derived from Mongolian horses. The genetic construction of each population appears to have been derived from independent breeding in each local area since the time of population fission, and this was accompanied by drastic genetic drift in recent times. This information will help to elucidate the ancestry of Japanese native horses.
    Biochemical Genetics 05/2007; 45(3-4):375-95. · 0.86 Impact Factor
  • Article: High-resolution gene maps of horse chromosomes 14 and 21: additional insights into evolution and rearrangements of HSA5 homologs in mammals.
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    ABSTRACT: High-resolution physically ordered gene maps for equine homologs of human chromosome 5 (HSA5), viz., horse chromosomes 14 and 21 (ECA14 and ECA21), were generated by adding 179 new loci (131 gene-specific and 48 microsatellites) to the existing maps of the two chromosomes. The loci were mapped primarily by genotyping on a 5000-rad horse x hamster radiation hybrid panel, of which 28 were mapped by fluorescence in situ hybridization. The approximately fivefold increase in the number of mapped markers on the two chromosomes improves the average resolution of the map to 1 marker/0.9 Mb. The improved resolution is vital for rapid chromosomal localization of traits of interest on these chromosomes and for facilitating candidate gene searches. The comparative gene mapping data on ECA14 and ECA21 finely align the chromosomes to sequence/gene maps of a range of evolutionarily distantly related species. It also demonstrates that compared to ECA14, the ECA21 segment corresponding to HSA5 is a more conserved region because of preserved gene order in a larger number of and more diverse species. Further, comparison of ECA14 and the distal three-quarters region of ECA21 with corresponding chromosomal segments in 50 species belonging to 11 mammalian orders provides a broad overview of the evolution of these segments in individual orders from the putative ancestral chromosomal configuration. Of particular interest is the identification and precise demarcation of equid/Perissodactyl-specific features that for the first time clearly distinguish the origins of ECA14 and ECA21 from similar-looking status in the Cetartiodactyls.
    Genomics 02/2007; 89(1):89-112. · 3.02 Impact Factor
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    Article: Polymorphism identification, RH mapping, and association analysis with the anxiety trait of the equine serotonin transporter (SLC6A4) gene.
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    ABSTRACT: Equine anxiety trait is considered an important temperament in various situations, including riding, training, and daily care. This study examined the polymorphism of the equine serotonin transporter (SLC6A4) gene as a candidate genetic element influencing equine anxiety trait. The sequence of the coding region of this gene was highly homologous with those of other mammals, and four single nucleotide polymorphisms were found by comparing the sequences of ten genetically unrelated thoroughbred horses. Radiation hybrid mapping revealed that this gene was located 26.92 cR from neurofibromin 1 on ECA 11. Using two-year-old thoroughbred horses (n=67), the association of these polymorphisms with the anxiety trait was examined, but no significant association was identified between each haplotype of the serotonin transporter gene and the anxiety score.
    Journal of Veterinary Medical Science 07/2006; 68(6):619-21. · 0.85 Impact Factor
  • Article: Association of a C/T single-nucleotide polymorphism in the 5' untranslated region of the CD40 gene with Graves' disease in Japanese.
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    ABSTRACT: Graves' disease (GD) is caused by an interplay of genetic factors and environmental triggers. Recently, a susceptibility locus for GD was mapped to chromosome 20q11 (GD-2). Furthermore, a novel single nucleotide polymorphism (SNP) in the CD40 gene, which is located in 20q11, was found to be associated and linked with GD in Caucasians and in Koreans. To examine a C/T SNP in the 5' untranslated region of the CD40 gene (CD40-E1SNP) for association with autoimmune thyroid diseases (AITDs) in a Japanese dataset. Case-control association studies were performed using the CD40-E1SNP. We studied 485 Japanese patients with AITD (301 with GD, 184 with Hashimoto's thyroiditis [HT]) and 177 matched Japanese control subjects in association studies. Frequencies of genotypes and alleles of the CD40- E1SNP. The distribution of genotype frequencies differed significantly between patients with GD and controls in a dominant manner (p = 0.039). The CC+CT genotypes of the CD40-E1SNP were associated with the increased risk for GD (p = 0.015, odds ratio [OR] = 1.9). In contrast, no differences in genotype frequencies were observed between HT patients and controls for the CD40-E1SNP. These results suggested that the CD40 gene is involved in susceptibility for GD in the Japanese.
    Thyroid 06/2006; 16(5):443-6. · 4.79 Impact Factor
  • Article: Single linkage group per chromosome genetic linkage map for the horse, based on two three-generation, full-sibling, crossbred horse reference families.
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    ABSTRACT: A genetic linkage map of the horse consisting of 742 markers, which comprises a single linkage group for each of the autosomes and the X chromosome, is presented. The map has been generated from two three-generation full-sibling reference families, sired by the same stallion, in which there are 61 individuals in the F2 generation. Each linkage group has been assigned to a chromosome and oriented with reference to markers mapped by fluorescence in situ hybridization. The average interval between markers is 3.7 cM and the linkage groups collectively span 2772 cM. The 742 markers comprise 734 microsatellite and 8 gene-based markers. The utility of the microsatellite markers for comparative mapping has been significantly enhanced by comparing their flanking sequences with the human genome sequence; this enabled conserved segments between human and horse to be identified. The new map provides a valuable resource for genetically mapping traits of interest in the horse.
    Genomics 02/2006; 87(1):1-29. · 3.02 Impact Factor
  • Article: The codon 620 single nucleotide polymorphism of the protein tyrosine phosphatase-22 gene does not contribute to autoimmune thyroid disease susceptibility in the Japanese.
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    ABSTRACT: The etiology of the autoimmune thyroid diseases (AITDs), Graves' disease (GD), and Hashimoto's thyroiditis (HT) is largely unknown. However, genetic susceptibility is believed to play a major role. The lymphoid tyrosine phosphatase (LYP), encoded by the protein tyrosine phosphatase-22 (PTPN22) gene, is a powerful inhibitor of T cell activation. Recently, a single-nucleotide polymorphism (SNP), encoding a functional arginine to tryptophan residue change at PTPN22 codon 620 in Caucasians has been shown to be associated with GD and other autoimmune diseases. We have used a polymerase chain reaction (PCR)-restriction fragment (XcmI) assay to examine genotypes at the codon 620 polymorphism in 334 unrelated patients with AITD and 179 controls. None of the patients with AITD and controls had the tryptophan allele. These data suggest that the codon 620 polymorphism of the PTPN22 gene does not have a causal role for AITD in the Japanese. However, we cannot exclude the PTPN22 region as harboring another susceptibility locus for AITD in linkage disequilibrium with the Trp/Arg SNP.
    Thyroid 11/2005; 15(10):1115-8. · 4.79 Impact Factor

Institutions

  • 2002–2011
    • Laboratory of Racing Chemistry
      Tochigi, Tochigi-ken, Japan
  • 2002–2010
    • Showa University
      • • Department of Internal Medicine
      • • Third Department of Internal Medicine
      • • School of Pharmaceutical Sciences
      Shinagawa-ku, Japan
  • 2005–2007
    • Texas A&M University
      • Department of Veterinary Integrative Biosciences
      College Station, TX, USA