Mucopolysaccharidosis IVA: four new exonic mutations in patients with N-acetylgalactosamine-6-sulfate sulfatase deficiency.

We report four new mutations in Japanese patients with mucopolysaccharidosis IVA (MPSIVA) who were heterozygous for a common double gene deletion. A nonsense mutation of CAG to TAG at codon 148 in exon 4 was identified, resulting in a change of Q to a stop codon and three missense mutations. V (GTC) to A (GCC) at codon 138 in exon 4, P (CCC) to S (TCC) at codon 151 in exon 5, and P (CCC) to L (CTC) at codon 151 in exon 5.

Incidence of peroxisomal disorders in Japan.

Japanese patients with peroxisomal disorders in the pediatric field were screened. Very long chain fatty acid analysis in the serum sphingomyelin was introduced since 1987 and was useful for the first screening of peroxisomal disorders. Seventy-five patients were diagnosed since 1980: 15 patients with Zellweger syndrome, 2 with neonatal adrenoleukodystrophy (ALD), 1 with rhizomelic chondrodysplasia punctata, 1 with Zellweger-like syndrome.

Prenatal diagnosis of adrenoleukodystrophy by means of mutation analysis.

Prenatal diagnosis of adrenoleukodystrophy (ALD) was performed by means of genetic and biochemical analysis using chorionic villi and amniocytes. The mother was a carrier of an exonic point mutation in the ALD protein gene (2154 C to T) which resulted in the premature formation of a termination codon (Q590STOP) and deletes the Pst I site. Two patients in this family were hemizygotes for this mutation.

Mucopolysaccharidosis IVA: submicroscopic deletion of 16q24.3 and a novel R386C mutation of N-acetylgalactosamine-6-sulfate sulfatase gene in a classical Morquio disease.

The N-acetylgalactosamine-6-sulfate sulfatase (GALNS) gene, which is responsible for autosomal recessive mucopolysaccharidosis IVA (MPSIVA), has been assigned to the long arm of chromosome 16, subregion 24.3, an area where the adenine phosophoribosyltransferase (APRT) gene and renal dipeptidase (DPEP I) gene are also localized. Molecular genetic studies on a severely affected patient with MPSIVA (Morquio disease), without karyotypic abnormality, revealed a partial submicroscopic deletion of 16q24.

Mucopolysaccharidosis IVA: a comparative study of polymorphic DNA haplotypes in the Caucasian and Japanese populations.

Mucopolysaccharidosis IVA (MPS IVA) is an autosomal recessive disorder caused by deficiency of the lysosomal enzyme N-acetylgalactosamine-6-sulphate sulphatase (GALNS). The genetic heterogeneity at the GALNS locus was studied in 62 mutant alleles and 376 normal alleles in the Caucasian population and also in 40 mutant and 100 normal alleles in the Japanese population. For this study, six different restriction fragment length polymorphisms (RFLPs) at the GALNS locus were analysed to search for the frequency of each RFLP produced by StyI, SphI, RsaI, HaeIII, StuI and HapII restriction endonucleases.

Mucopolysaccharidosis type I: identification of common mutations that cause Hurler and Scheie syndromes in Japanese populations.

alpha-L-Iduronidase (IDUA) deficiency (mucopolysaccharidosis type I; MPS-I) is an inborn error of lysosomal degradation of glycosaminoglycans that results in storage of undegraded glycosaminoglycans in lysosomes. Previous studies in Caucasian populations showed that (1) homozygosity or compound heterozygosity for the W402X and Q70X mutations are the common causes of MPS-I with a severe form (Hurler syndrome), and (2) the presence of R89Q may lead to a milder phenotype. We studied mutations in the IDUA gene from 19 MPS-I patients, including two pairs of siblings, with various clinical phenotypes (Hurler, 6 cases; Hurler/Scheie, 7 cases; Scheie, 6 cases).

Peroxisome assembly factor-2, a putative ATPase cloned by functional complementation on a peroxisome-deficient mammalian cell mutant.

Rat peroxisome assembly factor-2 (PAF-2) cDNA was isolated by functional complementation of peroxisome deficiency of a mutant CHO cell line, ZP92, using transient transfection assay. This cDNA encodes a 978-amino acid protein with two putative ATP-binding sites. PAF-2 is a member of a putative ATPase family, including two yeast gene products essential for peroxisome assembly.

Peroxisomal assembly defects: clinical, pathologic, and biochemical findings in two patients in a newly identified complementation group.

We describe the clinical, pathologic, and biochemical findings for two peroxisome-deficient patients in a newly identified complementation group. Both patients had biochemical findings typical of patients with peroxisome biogenesis disorders. However, whereas one patient had the typical clinicopathologic features of Zellweger syndrome, the other patient's phenotype was atypical.

Adrenoleukodystrophy: the restoration of peroxisomal beta-oxidation by transfection of normal cDNA.

In order to elucidate the function of ALDP [a protein encoded by the gene responsible for adrenoleukodystrophy (ALD)], normal ALDP cDNA, inserted in an expression vector driven by chicken beta-actin promotor, was transfected into ALD fibroblasts. In a transient expression system, the fatty acid composition did not change even though the ALDP was newly synthesized based on the findings of a western blot analysis. In a stable expression system, 3 cell lines were strongly positive for ALDP.

Mucopolysaccharidosis type IVA: common double deletion in the N-acetylgalactosamine-6-sulfatase gene (GALNS).

Mucopolysaccharidosis IVA (MPS IVA) is an autosomal recessive disorder caused by a deficiency in N-acetylgalactosamine-6-sulfatase (GALNS). We found two separate deletions of nearly 8.0 and 6.

Mucopolysaccharidosis IVA: screening and identification of mutations of the N-acetylgalactosamine-6-sulfate sulfatase gene.

Mutations causing mucopolysaccharidosis IVA in 15 Japanese and one Caucasian patient were characterized. To screen these mutations, we used a combination of single strand conformation polymorphism analysis and heteroduplex analysis for PCR products of targeted cDNA or genomic DNA. Various small mutations were identified in 23 of 26 alleles, while the other six alleles had large rearrangements.

Polymerase chain reaction detection of two novel human N-acetylgalactosamine-6-sulfate sulfatase gene polymorphisms by single-strand conformation polymorphism analysis or by StyI and StuI cleavages.

We describe two common single-base polymorphisms of the N-acetylgalactosamine-6-sulfate sulfatase gene after StyI or StuI restriction sites. These polymorphisms were readily detected by single-strand conformation polymorphism (SSCP), using the polymerase chain reaction (PCR).

Effects of erucic acid therapy on Japanese patients with X-linked adrenoleukodystrophy.

Ten Japanese boys with childhood adrenoleukodystrophy (ALD), one adult patient with adrenomyeloneuropathy (AMN), and two presymptomatic ALD boys were treated with dietary erucic acid (C22:1) for more than 12 months; except in a case of childhood ALD patient who died 7 months after beginning erucic acid therapy. During erucic acid therapy, the serum levels of very long-chain fatty acid (VLCFA) (C24:0/C22:0) decreased within 1-2 months in all patients, and these levels in four of the patients decreased to the normal range. Neurological examination and MRI findings in all 10 of the childhood ALD patients showed progression of the disease while they were receiving the dietary therapy.

High-intensity proton and T2-weighted MRI signals in the globus pallidus in juvenile-type of dentatorubral and pallidoluysian atrophy.

Dentatorubral and pallidoluysian atrophy (DRPLA) is an autosomal dominant neurodegenerative disorder. An expanded CAG trinucleotide repeat sequence motif in a gene on the short arm of chromosome 12 has recently been identified in patients with DRPLA. Juvenile-type DRPLA is characterized by childhood onset and progressive myoclonic epilepsy (PME).

Suppression of IgA production by lymphocytes induced by diphenylhydantoin.

In this study, the mechanisms for suppression of immunoglobulin production by lymphocytes induced by diphenylhydantoin (DPH) were investigated using peripheral blood mononuclear cells from one patient 3 months after discontinuation of DPH, when IgA deficiency was improved. Immunoglobulin production in PBMCs was dose-dependently suppressed by DPH and the suppressive effect of DPH on IgA production tended to be greater than the effect on IgM or IgG production. Moreover, cell separation experiments indicated that DPH suppresses immunoglobulin production by PBMCs through a suppression of B cell, but not T cell, function.

Peroxisome assembly factor 1: nonsense mutation in a peroxisome-deficient Chinese hamster ovary cell mutant and deletion analysis.

A cDNA encoding 35-kDa peroxisome assembly factor 1 (PAF-1), a peroxisomal integral membrane protein, was cloned from Chinese hamster ovary (CHO) cells and sequenced. The CHO PAF-1 comprised 304 amino acids, one residue shorter than rat or human PAF-1, and showed high homology to rat and human PAF-1: 90 and 86% at the nucleotide sequence level and 92 and 90% in amino acid sequence, respectively. PAF-1 from these three species contains a conserved cysteine-rich sequence at the C-terminal region which is exactly the same as that of a novel cysteine-rich RING finger motif family.

Intravenous immunoglobulins suppress immunoglobulin productions by suppressing Ca(2+)-dependent signal transduction through Fc gamma receptors in B lymphocytes.

A high dose intravenous immunoglobulin (IVIG) therapy is used in the treatment of a wide range of autoimmune disorders. However, the mechanisms of the action of IVIGs remain poorly understood. To analyse the mechanisms of effects of IVIGs on immunoglobulin (Ig) production of B cells, the effects of IVIGs on B lymphoblastoid cell lines transformed by Epstein-Barr virus (LCLs) were investigated.

Short latency somatosensory evoked potentials and 99mTc-HMPAO SPECT in a case of flunarizine-effective alternating hemiplegia in infancy.

Short latency somatosensory evoked potentials (SSEPs) and 99mTc-hexamethylpropylene amine oxime single photon emission computed tomography (99mTc-HMPAO SPECT) were examined in a patient with alternating hemiplegia in infancy (AHI) before and after flunarizine treatment. The low amplitude and elongation of the latency time at the C'4 level of the interictal SSEPs before treatment were ameliorated by flunarizine administration. The cerebral hypoperfusion in the right hemisphere observed on 99mTc-HMPAO SPECT before treatment improved, as seen by normal and symmetrical imaging, after flunarizine treatment.

Comparison of allergic diseases and specific IgE antibodies in different parts of Japan.

We investigated the differences of allergic diseases and specific IgE antibodies to inhaled or ingested allergens between two cities in a Japanese pediatric population. One of the two cities is Itoman, which is a subtropical city in Okinawa prefecture; the other is Gifu, which is a Temperate Zone city in Gifu prefecture. The prevalence of asthma or wheezy bronchitis was significantly higher in Itoman; however, the prevalence of atopic dermatitis was significantly higher in Gifu.

A wild-type mu s C-terminal gene is expressed in Bloom's syndrome cells.

Selective IgM deficiency is found commonly in patients with Bloom's syndrome (BS). Serum IgM concentrations were low though serum IgG and IgA concentrations were normal in both patients with BS included in the study. In a previous study the authors showed that selective IgM deficiency in BS is due to an abnormality in the maturation of surface IgM-bearing cells into IgM-secreting cells and a failure of secreted mu (mu s) mRNA synthesis.

Mucopolysaccharidosis IV A: molecular cloning of the human N-acetylgalactosamine-6-sulfatase gene (GALNS) and analysis of the 5'-flanking region.

Mucopolysaccharidosis IV A (MPS IV A) is the result of a genetic deficiency in a lysosomal hydrolase, N-acetylgalactosamine-6-sulfatase (GALNS). To investigate MPS IV A patients at the level of the genome, we analyzed the structure of the human GALNS-encoding gene. From the genomic library of a normal subject in lambda EMBL3, we isolated five overlapping clones covering the coding region of the GALNS cDNA and determined the structural organization.