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Biomedical subjects

M Masuno

Publications and source records attributed to M Masuno.

At least 73 records · Page 4Linked to original sources

Median cleft of upper lip and pedunculated skin masses associated with de novo reciprocal translocation 46,X,t(X;16)(q28;q11.2).

We describe a de novo apparently balanced reciprocal translocation, 46,X,t(X;16)(q28;q11.2), in a 13 year old girl with median cleft of the upper lip, pedunculated skin masses on the nasal septum, short stature, and mental retardation. Pai syndrome is characterised by median cleft of the upper lip, pedunculated skin mass(es) on the face, and midline lipoma(s) of the central nervous system. The cause of this syndrome is unknown, although autosomal dominant inheritance has been proposed. The translocation breakpoints in the present patient may be candidate regions for a gene responsible for median cleft of the upper lip and pedunculated skin mass(es) on the face, including Pai syndrome.

Abnormalities, Multiple↗

Further delineation of renal-coloboma syndrome in patients with extreme variability of phenotype and identical PAX2 mutations.

Renal-coloboma syndrome is a recently described autosomal dominant syndrome of abnormal optic nerve and renal development. Two families have been reported with renal-coloboma syndrome and mutations of the PAX2 gene. The PAX2 gene, which encodes a DNA-binding protein, is expressed in the developing ear, CNS, eye, and urogenital tract. Ocular and/or renal abnormalities have been consistently noted in the five reports of patients with renal-coloboma syndrome, to date, but PAX2 expression patterns suggest that auditory and CNS abnormalities may be additional features of renal-coloboma syndrome. To determine whether additional clinical features are associated with PAX2 mutations, we have used PCR-SSCP to identify PAX2 gene mutations in patients. We report here four patients with mutations in exon 2, one of whom has severe ocular and renal disease, microcephaly, and retardation, and another who has ocular and renal disease with high-frequency hearing loss. Unexpectedly, extreme variability in clinical presentation was observed between a mother, her son, and an unrelated patient, all of whom had the same PAX2 mutation as previously described in two siblings with renal-coloboma syndrome. These results suggest that a sequence of seven Gs in PAX2 exon 2 may be particularly prone to mutation.

Abnormalities, Multiple↗

SPONASTRIME dysplasia: report on a female patient with severe skeletal changes.

We report on a 6-year-old girl with SPONASTRIME dysplasia, characterized by short-limbed dwarfism, a relatively large head, midfacial hypoplasia, a saddle nose, moderate deformities of the vertebral bodies, striated metaphyses, and normal intelligence. She showed severe skeletal changes including marked delay of epiphyseal ossification, evident metaphyseal dysplasia, and osteopathia striata more pronounced than in most of the previously reported patients with this disorder. The patient we describe and a male patient reported by Camera et al. [1994: Pediatr Radiol 24:322-324] are likely to represent the severely-affected end of the clinical spectrum of the disorder. These finding thus rule out the X-linked mode of inheritance of the disorder proposed by Camera et al. [1994: Pediatr Radiol 24: 322-324]. Alternatively, the two severely-affected patients may represent a variant form of the disorder. There is evidence that SPONASTRIME dysplasia is a genetically heterogeneous disorder.

Bone Diseases, Developmental↗

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 16q24.3 and a single point mutation on the other allele, with no functional GALNS activity. The patient, his mother, and siblings were hemizygous for GALNS and APRT loci, evidenced by informative RFLP and gene dosage analyses combined with a fluorescence in situ hybridization, utilizing a partial genomic clone of GALNS, but heterozygosity was retained at the DPEP I locus and proximal D16S7. Haplotyping of the family members revealed recombinational events between DPEP I locus and three other polymorphic loci on the paternal chromosome, localizing GALNS gene on the proximal side to DPEP I gene. As estimated from the genetic distance between two flanking markers of proximal D16S7 and distal DPEP I locus, size of the deletion was less than 3Mb. Mother of the boy and two older siblings were asymptomatic, despite this interstitial deletion of the Giemsa-light G band. The remaining paternal allele had no gene rearrangement but GALNS activity was not encoded as Arginine at 386 was replaced with Cysteine (R386C), suggesting this alteration accounts for the severe phenotype. Allelic loss of APRT is frequently observed in cancer tissues, thereby suggesting that the tumor suppressor gene locates near the APRT locus. No family member has evidence of any malignant disease. This study is apparently the first documentation of interstitial deletion of 16q24.3, involving GALNS and APRT genes.

Adenine Phosphoribosyltransferase↗

Life-threatening cardiac involvement throughout life in a case of Costello syndrome.

Costello syndrome is characterized by poor postnatal growth, mental retardation, curly hair, coarse face, loose skin of the hands and feet, and nasal papillomata. Patients with Costello syndrome have a high incidence of cardiac involvement, such as arrhythmias, hypertrophic cardiomyopathy, or congenital anomalies. The importance of cardiac involvement in Costello syndrome has not been strongly emphasized thus far, although arrhythmia and hypertrophic cardiomyopathy are both serious forms of cardiac involvement. We report the case of a Japanese girl with Costello syndrome, who experienced life-threatening cardiac involvement throughout her life.

Anus Neoplasms↗

Currarino triad with a terminal deletion 7q35-->qter.

We describe a de novo terminal deletion of the long arm of chromosome 7 in a 5 year old girl with the Currarino triad, characterised by congenital anorectal stenosis, a sacral defect, and a presacral mass. Recently, this autosomal dominant trait has been shown to be linked to 7q36, the same region as holoprosencephaly (HPE3). The cytogenetic findings in the present patient with the Currarino triad provided further evidence that a gene(s) for the Currarino triad is located in the 7 q terminal segment.

Abnormalities, Multiple↗

Human peroxisome assembly factor-2 (PAF-2): a gene responsible for group C peroxisome biogenesis disorder in humans.

Peroxisome-biogenesis disorders (PBD) are genetically heterogeneous and can be classified into at least ten complementation groups. We recently isolated the cDNA for rat peroxisome assembly factor-2 (PAF-2) by functional complementation using the peroxisome-deficient Chinese-hamster-ovary cell mutant, ZP92. To clarify the novel pathogenic gene of PBD, we cloned the full-length human PAF-2 cDNA that morphologically and biochemically restores peroxisomes of group C Zellweger fibroblasts (the same as group 4 in the Kennedy-Krieger Institute) and identified two pathogenic mutations in the PAF-2 gene in two patients with group C Zellweger syndrome. The 2,940-bp open reading frame of the human PAF-2 cDNA encodes a 980-amino-acid protein that shows 87.1% identity with rat PAF-2 and also restored the peroxisome assembly after gene transfer to fibroblasts of group C patients. Direct sequencing of the PAF-2 gene revealed a homozygous 1-bp insertion at nucleotide 511 (511 insT) in one patient with group C Zellweger syndrome (ZS), which introduces a premature termination codon in the PAF-2 gene, and, in the second patient, revealed a splice-site mutation in intron 3 (IVS3+1G-->A), which skipped exon 3, an event that leads to peroxisome deficiency. Chromosome mapping utilizing FISH indicates that PAF-2 is located on chromosome 6p21.1. These results confirm that human PAF-2 cDNA restores peroxisome of group C cells and that defects in the PAF-2 produce peroxisome deficiency of group C PBD.

ATPases Associated with Diverse Cellular Activitie↗

Miller-Dieker syndrome due to maternal cryptic translocation t(10;17) (q26.3;p13.3)

We report on a 3-month-old girl with Miller-Dieker syndrome resulting from a maternal full-cryptic translocation t(10;17) (q26.3;p13.3) detectable only by using fluorescence in situ hybridization (FISH). Parental studies using FISH are crucial for genetic counselling in cases of Miller-Dieker syndrome with submicroscopic deletion at 17p13.3. In a family with a parental cryptic translocation and high recurrence risk, parental diagnosis using FISH is feasible.

Abnormalities, Multiple↗

Hypoglycemia in Coffin-Siris syndrome.

We describe a further patient with the Coffin-Siris syndrome who presented at 4 months with recurrent hypoglycemia attacks. Detailed examination was undertaken at 7 months but the cause of hypoglycemia was not detected. Hypoglycemia seems to be a previously undescribed finding in the Coffin-Siris syndrome.

Abnormalities, Multiple↗

Rubinstein-Taybi syndrome caused by mutations in the transcriptional co-activator CBP.

The Rubinstein-Taybi syndrome (RTS) is a well-defined syndrome with facial abnormalities, broad thumbs, broad big toes and mental retardation as the main clinical features. Many patients with RTS have been shown to have breakpoints in, and microdeletions of, chromosome 16p13.3 (refs 4-8). Here we report that all these breakpoints are restricted to a region that contains the gene for the human CREB binding protein (CBP), a nuclear protein participating as a co-activator in cyclic-AMP-regulated gene expression. We show that RTS results not only from gross chromosomal rearrangements of chromosome 16p, but also from point mutations in the CBP gene itself. Because the patients are heterozygous for the mutations, we propose that the loss of one functional copy of the CBP gene underlies the developmental abnormalities in RTS and possibly the propensity for malignancy.

Amino Acid Sequence↗

Rieger syndrome with de novo reciprocal translocation t(1;4) (q23.1;q25).

We report on a boy with Rieger syndrome, who had an apparently balanced reciprocal translocation between chromosomes 1 and 4. The clinical manifestations of this patient were characterized by irregular shaped pupils with a prominent Schwalbe line and an umbilical hernia. On cytogenetic studies, he was found to have a de novo reciprocal translocation 46,XY,t(1;4) (q23.1;q25), without visible deletion. His parents had normal chromosomes. A review of both cytogenetic and genetic linkage analyses with Rieger syndrome showed that chromosome 4q was involved. This and other previous reports suggested that the gene for Rieger syndrome is mapped to the 4q25-->4q26 segment adjoining the breakpoint.

Abnormalities, Multiple↗

Autosomal dominant inheritance in Setleis syndrome.

Setleis syndrome is characterized by bitemporal skin depressions resembling forceps marks, abnormalities of the eyelashes, and "leonine" facial appearance. The cause is unknown, although autosomal recessive inheritance has been proposed. Recently, two families were reported in which one of the parents of a patient with Setleis syndrome showed mild manifestations, suggesting autosomal dominant inheritance. We describe a 9-month-old Japanese boy with typical Setleis syndrome. His father, who has normal intelligence, has bitemporal focal dermal dysplasia but a normal face. His paternal second cousin also has Setleis syndrome. This family shows autosomal dominant inheritance including father-to-son transmission of Setleis syndrome with variable expressivity and reduced penetrance. Careful examination of the relatives of patients with Setleis syndrome is recommended.

Adult↗

Shwachman syndrome associated with de novo reciprocal translocation t(6;12)(q16.2;q21.2).

We describe a de novo apparently balanced reciprocal translocation t(6;12)(q16.2; q21.2) in an 18 month old girl with Shwachman syndrome, characterised by exocrine pancreatic insufficiency and bone marrow dysfunction. The cause of this syndrome is unknown, although autosomal recessive inheritance has been proposed. The translocation breakpoints in the present patient may be candidate regions for a gene responsible for Shwachman syndrome.

Abnormalities, Multiple↗

Osteodysplastic primordial dwarfism: a case with features of type II.

We describe a 22-month-old Japanese girl with severe microcephaly with a prominent nose and a receding chin, developmental delay, marked intrauterine and postnatal dwarfism with limb shortening and brachydactyly, and distinctive radiological changes of the skeleton. The radiological findings include hypoplasia of the short tubular bones, multiple pseudoepiphyses in the bases of the metacarpals, coxa valga, a wide pelvis with iliac flaring, thoracolumbar scoliosis, and disharmonious ossification delay. The clinical and radiological features are somewhat different from those of previously reported cases with osteodysplastic primordial dwarfism. The clinical and radiological manifestations of osteodysplastic primordial dwarfism are reviewed and compared with those in our patient.

Dwarfism↗