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Kabuki syndrome is characterized by a variable degree of intellectual disability, characteristic facial features, and complications in various organs. Many variants have been identified in two causative genes, that is, lysine methyltransferase 2D (KMT2D) and lysine demethylase 6A (KDM6A). In this study, we present the results of genetic screening of 100 patients with a suspected diagnosis of Kabuki syndrome in our center from July 2010 to June 2018. We identified 76 variants (43 novel) in KMT2D and 4 variants (3 novel) in KDM6A as pathogenic or likely pathogenic. Rare variants included a deep splicing variant (c.14000-8C>G) confirmed by RNA sequencing and an 18% mosaicism level for a KMT2D mutation. We also characterized a case with a blended phenotype consisting of Kabuki syndrome, osteogenesis imperfecta, and 16p13.11 microdeletion. We summarized the clinical phenotypes of 44 patients including a patient who developed cervical cancer of unknown origin at 16 years of age. This study presents important details of patients with Kabuki syndrome including rare clinical cases and expands our genetic understanding of this syndrome, which will help clinicians and researchers better manage and understand patients with Kabuki syndrome they may encounter.

Kabuki syndrome is characterized by a variable degree of intellectual disability, characteristic facial features, and complications in various organs. Many variants have been identified in two causative genes, that is, lysine methyltransferase 2D (KMT2D) and lysine demethylase 6A (KDM6A). In this study, we present the results of genetic screening of 100 patients with a suspected diagnosis of Kabuki syndrome in our center from July 2010 to June 2018. We identified 76 variants (43 novel) in KMT2D and 4 variants (3 novel) in KDM6A as pathogenic or likely pathogenic. Rare variants included a deep splicing variant (c.14000-8CG) confirmed by RNA sequencing and an 18% mosaicism level for a KMT2D mutation. We also characterized a case with a blended phenotype consisting of Kabuki syndrome, osteogenesis imperfecta, and 16p13.11 microdeletion. We summarized the clinical phenotypes of 44 patients including a patient who developed cervical cancer of unknown origin at 16 years of age. This study presents important details of patients with Kabuki syndrome including rare clinical cases and expands our genetic understanding of this syndrome, which will help clinicians and researchers better manage and understand patients with Kabuki syndrome they may encounter.

Diamond-Blackfan anemia (DBA) is an inherited anemia with multiple congenital malformations, and mutations in ribosomal protein genes have been identified as the underlying cause. We describe a female patient with mild DBA due to 1p22 deletion, encompassing the gene encoding 60S ribosomal protein L5 (RPL5). Considering previously reported cases together with our patient, we suggest that RPL5 haploinsufficiency might cause a less severe form of DBA than loss-of-function mutations.

Peutz-Jeghers syndrome (PJS) is a rare autosomal dominant disease characterized by gastrointestinal polyposis and mucocutaneous pigmentation. Germline point mutations in the serine/threonine kinase 11 (STK11) have been identified in about 70% of patients with PJS. Only a few large genomic deletions have been identified. We report on a girl with PJS and multiple congenital anomalies. She had intellectual disability, umbilical hernia, bilateral inguinal hernias, scoliosis, and distinct facial appearance including prominent mandible, smooth philtrum, and malformed ears. She developed lip pigmentation at the age of 12 years but had no gastrointestinal polyps. Array comparative genomic hybridization revealed an approximately 610 kb deletion at 19p13.3, encompassing STK11. Together with previous reports, the identification of common clinical features suggests that microdeletion at 19p13.3 encompassing STK11 constitutes a distinctive phenotype.

17p13.1 Deletion encompassing TP53 has been described as a syndrome characterized by intellectual disability and dysmorphic features. Only one case with a 17p13.1 duplication encompassing TP53 has been reported in a patient with intellectual disability, seizures, obesity, and diabetes mellitus. Here, we present a patient with a 17p13.1 duplication who exhibited obesity and intellectual disability, similar to the previous report. The 9-year-old proposita was referred for the evaluation of intellectual disability and obesity. She also exhibited insulin resistance and liver dysfunction. She had wide palpebral fissures, upturned nostrils, a long mandible, short and slender fingers, and skin hyperpigmentation. Array comparative genomic hybridization (array CGH) detected a 3.2 Mb duplication of 17p13.1–p13.2 encompassing TP53, FXR2, NLGN2, and SLC2A4, which encodes the insulin-responsive glucose transporter 4 (GLUT4) associated with insulin-stimulated glucose uptake in adipocytes and muscle. We suggest that 17p13.1 duplication may represent a clinically recognizable condition characterized partially by a characteristic facial phenotype, developmental delay, and obesity. © 2014 Wiley Periodicals, Inc.

We report a 34-year-old Japanese female with the vascular type of Ehlers-Danlos syndrome. She had thin translucent skin, extensive bruising, toe joint hypermobility, left lower extremity varicose veins, and chronic wrist, knee and ankle joint pain. She also had dizziness caused by autonomic dysfunction. Magnetic resonance angiography showed tortuous vertebral and basilar arteries, mild left carotid canal bulging, and right anterior tibial artery hypoplasia. Electron microscopic examinations of a skin biopsy revealed extremely dilated rough endoplasmic reticulum in dermal fibroblasts and wide variability of individual collagen fibril diameters. A molecular analysis using a conventional total RNA method and a high-resolution melting curve analysis using genomic DNA revealed a novel missense mutation within exon 48 of the COL3A1 gene, c.3428G>A, leading to p.Gly1143Glu.

Tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein, epsilon polypeptide (YWHAE), on chromosome 17p13.3, has been shown to play a crucial role in neuronal development. The deletion of YWHAE, but not platelet-activating factor acetylhydrolase, isoform 1b, subunit 1 (PAFAH1B1), underlies a newly recognized neurodevelopmental disorder, characterized by significant growth retardation, developmental delay/intellectual disability (DD/ID), distinctive facial appearance, and brain abnormalities. Here, we report on a girl with a terminal deletion of 17p13.3, including YWHAE but not PAFAH1B1, showing normal brain structure on MRI. She had mild developmental delay, a distinctive facial appearance, and severe growth retardation despite normal growth hormone levels, which was improved by growth hormone therapy. Expression analysis of YWHAE and PAFAH1B1 yielded results consistent with array CGH and FISH results. These results indicate that the dosage effect of YWHAE varies from severe to very mild structural brain abnormalities, and suggest that the expression of YWHAE is associated with a complex mechanism of neuronal development.

Down syndrome is an autosomal chromosome disorder, characterized by intellectual disability and muscle hypotonia. Muscle hypotonia is observed from neonates to adulthood in Down syndrome patients, but muscle hypertonicity is extremely unusual in this syndrome. During a study period of nine years, we found three patients with severe spastic quadriplegia among 20 cases with Down syndrome and congenital duodenal stenosis/atresia (3/20). However, we could find no patient with spastic quadriplegia among 644 cases with Down syndrome without congenital duodenal stenosis/atresia during the same period (0/644, P

We report a female fetus with sirenomelia with 46,X,t(X;16)(p11.23;p12.3) de novo. Fluorescence in situ hybridization (FISH) with bacterial artificial chromosomes were employed for narrowing down the breakpoint regions. On chromosome 16, the breakpoint was mapped in the region of RP11-453F10 (19 920 640-20 118 153 bp from 16pter). On chromosome X, the breakpoint was mapped in the region of RP11-794A15 (47 333 744-47 524 066 bp from Xpter). This is the first case report of sirenomelia associated with translocations. The abnormal phenotype, associated with a balanced translocation, was caused by deletion or breakage of dosage-sensitive genes of the breakpoint, disruption of an imprinted gene, or uniparental disomy. Although the parental origin of normal 16 and der(16) remained undetermined, this case will provide insight into the pathogenetic mechanism of sirenomelia.

We report the case of a boy with a de novo partial monosomy 16p13-pter and partial trisomy 16q22-qter detected by fluorescence in situ hybridization using subtelomeric probes for 16p and 16q. The boy had facial characteristics, skeletal features, congenital heart defects, an imperforate anus, urogenital malformations, pre/postnatal growth retardation, and psychomotor retardation, most of which have been reported both in partial monosomy 16p and partial trisomy 16q. In addition, he suffered from upper airway stenosis due to possible laryngeal stenosis with subglottic webs. The upper airway stenosis could be a rare complication of partial monosomy 16p or partial trisomy 16q, or a nonspecific malformation resulting from chromosomal abnormalities.

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.

The purpose of the study was to identify risk and protective factors for child-related strain among Japanese mothers. The present study focused not only on mothers’ employment status and gender role attitudes, but also on partner’s gender role attitudes. A sample of 322 married Japanese couples (mean age: 31.2 years for mothers and 34.0 years for fathers) in Gifu, Japan, completed a self-administered questionnaire concerning child-related strain, number of children, distance from their parents, employment status, educational level, marital quality, and gender role attitudes. Results from multiple regression analyses showed that, among the mother’s variables, employment status and marital quality were negatively associated with child-related strain. The number of years of education was also negatively associated with child-related strain. Except for years of education, partner’s variables did not have strong effects on child-related strain. For Japanese mothers of toddlers, working may be protective against child-related strain.

Sotos syndrome is a well-known anomaly syndrome characterized by overgrowth, characteristic facial gestalt, and developmental delay, and haploinsufficiency of the NSD1 gene has been revealed as one of the major genetic causes. However, there have been only a few reports on neuroradiologic findings by computed tomography (CT) or magnetic resonance imaging (MRI), and functional examination of the brain has not been reported. We examined three cases with typical Sotos syndrome, which also were confirmed by genetic analysis with a specific probe for the NSD1 gene. The results of MRI showed the characteristic features that have been reported previously. The findings obtained by using single-photon emission computed tomography and magnetic resonance spectroscopy suggested an association between mental delay and behavioral tendency in Sotos syndrome and immaturity in frontal brain function. (J Child Neurol 2006;21:614—618; DOI 10.2310/7010.2006.00145).

The 1p36 deletion syndrome is a newly delineated multiple congenital anomalies/mental retardation syndrome characterized by mental retardation, growth delay, epilepsy, congenital heart defects, characteristic facial appearance, and precocious puberty. We analyzed 11 patients by fluorescence in situ hybridization (FISH) using commercially available bacterial artificial chromosome and P1-derived artificial chromosome genomic clones to define the chromosomal deletion responsible for the 1p36 deletion syndrome. Cytogenetic investigation revealed two cases with a terminal deletion of 1p36. Nine patients had an apparently normal karyotype with standard G-bands by trypsin using Giemsa (GTG), but FISH screening with the highly polymorphic genetic marker D1Z2, which is mapped to 1p36.3 and contains an unusual reiterated 40-bp variable number tandem repeat, revealed a submicroscopic deletion. All patients had severe to profound mental retardation. Based on the University of California Santa Cruz Genome Browser, we constructed a deletion map and analyzed the relationship between neurological findings and chromosomal deletions for the 11 cases. Six cases had intractable epilepsy and three had no seizures. The common deletion interval was about 1 million base pairs (Mbp) located between RP11-82D16 and RP4-785P20 (Rho guanine exchange factor (GEF) 16). The severity of clinical symptoms correlates with the size of the deletion. This is demonstrated by the 3 patients with at least 8Mbp deletions that display profound mental retardation and congenital heart defects. Although haploinsufficiency of the potassium channel beta-subunit (KCNAB2) is thought to be responsible for intractable seizures in the 1p36 deletion syndrome, this was not the case for 3 of the 11 patients in this study. Further investigation of the 1p36 region is necessary to allow identification of genes responsible for the 1p36 deletion syndrome.

Rubinstein-Taybi syndrome (RTS; MIM# 180849) is a well-known malformation syndrome, characterized by broad thumbs and halluces, a characteristic facies, short stature, and mental retardation. RTS is accompanied by a variety of morbid complications, particularly of the skeleton. Based on the experience of five RTS patients with malformation of the craniovertebral junction, we draw attention to previously unrecognized life-threatening complications of RTS, including instability of C1-C2, os odontoideum, hypoplasia of the dens, and fusion of the cervical vertebrae. One patient developed severe cervical myelopathy. Malformation of the cervical spine may be a common syndromic constituent of RTS, to which special attention should be paid to prevent its neurologic sequelae.

We describe an unusual case of congenital primitive epithelial tumor of the liver with focal rhabdoid features. The present case is unique and informative in the following aspects: (1) a first case of congenital epithelial tumor of the liver with no hepatocytic differentiation but focal rhabdoid features, (2) clinical similarities to multicentric hemangioma or stage 4S neuroblastoma, (3) diagnosis obtained from histological examination of the placenta immediately after birth.

Shwachman-Diamond syndrome is a rare genetic disorder of unknown pathogenesis involving exocrine pancreatic insufficiency and hematological and skeletal abnormalities. There is broad clinical variability; the extent of heterogeneity is unknown but comparisons within a large cohort of patients show no striking differences between patients of families with single or multiple affected offspring. Segregation analysis of a cohort of 69 families has suggested an autosomal recessive mode of inheritance. A single constitutional de novo chromosome rearrangement was reported in a Japanese patient involving a balanced translocation, t(6;12)(q16.2;q21.2), thereby suggesting possible loci for a genetic defect. Evenly spaced microsatellite markers spanning 26-32 cM intervals from D6S1056 to D6S304 and D12S375 to D12S346 were analyzed for linkage in members of 13 Shwachman-Diamond syndrome families with two or three affected children. Two-point lod scores were calculated for each marker under assumptions of recessive inheritance and complete penetrance. Negative lod scores indicated exclusion of both chromosome regions. Further, affected sibs were discordant for inheritance of chromosomes in most families based on constructed haplotypes. The cytogenetic abnormality is not associated with most cases of Shwachman-Diamond syndrome.

Shwachman syndrome is an autosomal-recessive disorder characterized by exocrine pancreatic insufficiency, bone-marrow dysfunction, and metaphyseal chondrodysplasia. A de novo balanced translocation was recently documented in a patient with this disease. Toward isolating the gene(s) responsible for Shwachman syndrome, we cloned and sequenced the translocation breakpoints in the DNA of this patient. The nucleotide sequences around the breakpoints contained neither repetitive elements nor motifs reported to be implicated in recombination events, although we did detect gains or losses of oligonucleotides at the translocation junctions. By large-scale genomic sequencing and in silico gene trapping, we identified two novel transcripts in the vicinity of the breakpoints that might represent candidate genes for Shwachman syndrome, one on chromosome 6 and the other on chromosome 12. The gene on chromosome 12 was actually disrupted by the translocation.

This study reports on Y chromosomal genotypes of three patients with gonadoblastoma and one patient with gonadoblastoma and mixed germ cell tumor. Molecular analysis for 35 Y chromosomal loci was performed for DNA samples taken from peripheral leukocytes and lymphoblastoid cell lines, showing that the four patients shared the region between DYS267 at interval 4A and DYF50S1 at interval 6D, with the exception of the region around DYS202 at interval 5K. In the patient with gonadoblastoma and mixed germ cell tumor, Y chromosomal material was preserved in the gonadoblastoma but was lost from the mixed germ cell tumor. The results, in conjunction with previous reports, suggest that GBY (gonadoblastoma locus on the Y chromosome) may be located to a roughly 5-Mb pericentromeric region between DYS267 at interval 4A and DYS270 at interval 5A. The presence of Y chromosomal material in gonadoblastoma is consistent with GBY being involved in the development of gonadoblastoma, and the absence of Y chromosomal material in mixed germ cell tumor would be explained as a consequence of Y chromosomal loss from rapidly proliferating gonadal cancer cells.

Fanconi anemia (FA) is an autosomal recessive disorder characterized by pancytopenia, predisposition to cancers, and a diverse variety of congenital malformations. At least eight complementation groups, A through H, have been described. Recently, the FA-A gene (FAA) has been isolated, and a large number of distinct mutations reported in ethnically diverse FA-A patients. Here, we report on the mutation analysis of five FA patients by single-strand conformation polymorphism. Out of five patients, at least three were found to have mutations in the FAA gene. The first patient was a compound heterozygote with a 1-bp deletion and a single-base substitution. The second patient had a heterozygous 2-bp deletion, which introduces a premature termination codon, and the third patient had a heterozygous splice donor site mutation in intron 27.

The phenotypes of chromosomal 22q11.2 microdeletion are quite variable among individuals and hypoparathyroidism (HP) constitutes a definite portion of the clinical spectrum. For the correct diagnosis and pertinent follow up of the HP children due to del22q11.2, we tried to delineate the clinical characteristics of such patients. By employing fluorescence in situ hybridization (FISH) to all the patients diagnosed as HP in our clinic, ten possessed the 22q11.2 microdeletion. Among them, the incidence of cardiac defect (5/10), recurrent infection (1/10) and cleft palate (1/10) was modest. Additionally, seven of them had been diagnosed as HP during the infantile period, when their facial abnormality and intellectual problem had not become evident. Notably, two patients were complicated by Graves disease, while the association of idiopathic thrombocytopenic purpura was also observed in two girls.HP due to del22q11.2 may be misdiagnosed as idiopathic, especially in an infant who lacks apparent complications like cardiac anomaly. They should be closely followed up for auto-immune complications.

We report two sporadic cases of a hitherto undescribed skeletal dysplasia with short stature and characteristic facies. The present patients, a 6-year-old girl and a 15-year-old boy, were almost equally affected. Craniofacial anomalies included a sloping forehead, bitemporal bulging, sparse medial eyebrows, a prominent nasal bridge, hypertelorism, proptosis, a beaked nose, hypoplastic alae nasi and a pointed chin. Shallow orbits, short anterior cranial fossae and bitemporal bossing found on skull radiograph corresponded with the facial dysmorphism. Thickening of the dorsum sellae was another hallmark in the skull. Skeletal survey revealed mild osteopenia, interpediculate narrowing of the lumbar spine with short neural arches and, most important, osteopathia striata of the long tubular bones. There was no sclerosis of the craniofacial bones. The clinical and radiological findings in the present patients were overall inconsistent with those of previously known skeletal dysplasias and congenital malformation syndromes, which possess osteopathia striata as a cardinal feature.The unique clinical and radiological constellation of our patients constitutes a hitherto unknown bone dysplasia.

Hunter disease is an X-linked recessive mucopolysaccharide storage disorder caused by iduronate-2-sulfatase deficiency and is rare in females. We describe here findings in a girl with Hunter disease of the severe type. She had a normal karyotype but a marked deficiency of iduronate-2-sulfatase activity in lymphocytes and cultured fibroblasts. In a sequence analysis of the iduronate-2-sulfatase gene, evidence was obtained for the R468Q (G1403 to A) mutation, a common one in Hunter disease. RT-PCR showed her cDNA to represent only the R468Q allele, although at the genomic level she was a heterozygote with one normal allele. Her brother had the R468Q mutation, and their mother was a carrier of this mutation. The fusion products of CHO (TG(R),Neo(R)) with patient's fibroblasts cultured in HAT/G418 selective medium, carried only the maternal allele. However, in genomic DNA from the patient's fibroblasts, only the paternal allele of the androgen receptor gene, a gene subjected to differential methylation of the inactive X-chromosome, was methylated. These findings strongly suggest that the severe form of Hunter disease in this girl was the result of selective expression of the maternal allele carrying the missense mutation R468Q, which in turn resulted from skewed X inactivation of the paternal nonmutant X chromosome.

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 findings 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. © 1996 Wiley-Liss, Inc.

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 features1-3. Many patients with RTS have been shown to have breakpoints in, and microdeletions of, chromosome 16pl3.3 (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-A IMP-regulated gene expression9-12. 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.

We report a 34-year-old Japanese female with the vascular type of Ehlers-Danlos syndrome. She had thin translucent skin, extensive bruising, toe joint hypermobility, left lower extremity varicose veins, and chronic wrist, knee and ankle joint pain. She also had dizziness caused by autonomic dysfunction. Magnetic resonance angiography showed tortuous vertebral and basilar arteries, mild left carotid canal bulging, and right anterior tibial artery hypoplasia. Electron microscopic examinations of a skin biopsy revealed extremely dilated rough endoplasmic reticulum in dermal fibroblasts and wide variability of individual collagen fibril diameters. A molecular analysis using a conventional total RNA method and a high-resolution melting curve analysis using genomic DNA revealed a novel missense mutation within exon 48 of the COL3A1 gene, c.3428GA, leading to p.Gly1143Glu.

Chromosomal abnormalities involving 19p13.3 have rarely been described in the published literature. Here, we report on a girl with a pure terminal duplication of 6.1 Mb on 19p13.3, caused by an unbalanced translocation der(19)t(10;19)(qter;p13.3)dn. Her phenotype included severe psychomotor developmental delay, skeletal malformations, and a distinctive facial appearance, similar to that of a patient previously reported by Lybaek et al. [Lybaek et al. (2009); Eur J Hum Genet 17:904-910]. These results suggest that a duplication of >3 Mb at the terminus of 19p13.3 might represent a distinct chromosomal syndrome.

We report a female fetus with sirenomelia with 46,X,t(X;16)(p11.23;p12.3) de novo. Fluorescence in situ hybridization (FISH) with bacterial artificial chromosomes were employed for narrowing down the breakpoint regions. On chromosome 16, the breakpoint was mapped in the region of RP11-453F10 (19 920 640-20 118 153 bp from 16pter). On chromosome X, the breakpoint was mapped in the region of RP11-794A15 (47 333 744-47 524 066 bp from Xpter). This is the first case report of sirenomelia associated with translocations. The abnormal phenotype, associated with a balanced translocation, was caused by deletion or breakage of dosage-sensitive genes of the breakpoint, disruption of an imprinted gene, or uniparental disomy. Although the parental origin of normal 16 and der(16) remained undetermined, this case will provide insight into the pathogenetic mechanism of sirenomelia.

Down syndrome is an autosomal chromosome disorder, characterized by intellectual disability and muscle hypotonia. Muscle hypotonia is observed from neonates to adulthood in Down syndrome patients, but muscle hypertonicity is extremely unusual in this syndrome. During a study period of nine years, we found three patients with severe spastic quadriplegia among 20 cases with Down syndrome and congenital duodenal stenosis/atresia (3/20). However, we could find no patient with spastic quadriplegia among 644 cases with Down syndrome without congenital duodenal stenosis/atresia during the same period (0/644, P 0.05). Further, we did not find any cases with spastic quadriplegia among 17 patients with congenital duodenal stenosis/atresia without Down syndrome admitted during the same period to use as a control group (0/17, P 0.05). Our results suggest that congenital duodenal stenosis/atresia is a potential risk factor for spastic quadriplegia in patients with Down syndrome. Long-term survival is improving, and the large majority of people with Down syndrome are expected to live well into adult life. Management and further study for the various problems, representing a low prevalence but serious and specific to patients with Down syndrome, are required to improve their quality of life.

Limb-body wall complex is a malformation of body and limbs with craniofacial defects. We describe here the epidemiology of this complex using the population-based registry data in the Kanagawa Birth Defects Monitoring Program during the period 1982-1991. Eleven infants (11/428,599 births) with the complex were ascertained in the study. The incidence and spectrum of the defects observed in our cases were similar to those of other studies. The parental ages in the study group were not significantly different from those in the general population. No teratogenic agents and factors were identified in the present study. Most cases were diagnosed prenatally.

Basal cell nevus syndrome (BCNS; Gorlin syndrome) is an autosomal dominant disorder, characterized by a predisposition to neoplasms and developmental abnormalities. BCNS is caused by mutations in the human homolog of the Drosophila patched gene-1, PTCH1, which is mapped on chromosome 9q22.3. Nonsense, frameshift, in-frame deletions, splice-site, and missense mutations have been found in the syndrome. Haploinsufficiency of PTCH1, which is caused by interstitial deletion of 9q22.3, is also responsible for the syndrome. To date, 19 cases with interstitial deletion of long arm of chromosome 9 involving the region of q22 have been reported. We describe two unrelated patients with some typical features of BCNS associated with deletion of 9q21.33-q31.1 and determined the boundary of the deletion by fluorescence in situ hybridization (FISH) with bacterial artificial chromosome (BAC) clones. The results showed that the size of deletions is between 15.33 and 16.04 Mb in patient 1 and between 18.08 and 18.54 Mb in patient 2. Although the size and breakpoints were different from those of previously reported cases, the clinical features are common to patients with 9q22 deletion associated with BCNS. Delineation of the 9q22 deletions and further consideration of the genes responsible for the characteristic manifestations may provide insight into this newly recognized deletion syndrome.

An 11-year-old-girl with silent thyroiditis associated with a transient increase in serum IgM and thyroid hormone is described. The levels of serum IgM decreased from 4.38 g/L to 3.35 g/L after 1.5 months at the same time as thyroid hormones returned to normal. An unidentified antecedent infection or exposure to antigen causing the increase in serum IgM might have triggered the occurrence of silent thyroiditis in this patient, although a search for viral antibodies revealed no significant titer changes during the course of the disease.

We report on two new patients who had unilateral microphthalmia and esophageal atresia. A similar association was previously described in six patients. The accumulation of the eight affected patients provides further support for recognizing this association as a distinct syndrome.

We present two patients with multiple characteristics that occur in Noonan phenotype and cavernous hemangioma of the brain. The first patient, who had been diagnosed radiographically as having a cavernous hemangioma in the left basal ganglia at age 15 years, developed massive intracerebral hemorrhage, resulting in sudden death at home at 19 years. The second patient, who was diagnosed radiographically as having a cavernous hemangioma in the left parietal lobe at age 17 years, is being followed carefully (the patient is currently 18 years old). A review disclosed four cases of structural cerebrovascular abnormalities with or without subsequent hemorrhage. Neither these four patients nor our two patients had any severe anomalies in the heart or large vessels, which are frequently seen in patients with Noonan syndrome. Cerebrovascular abnormalities might have a significant influence on the prognosis of patients with Noonan syndrome, especially those having no severe abnormalities in the heart or large vessels.

Rubinstein-Taybi syndrome (RTS, MIM 180849) is a multiple malformation syndrome characterized by growth retardation, developmental delay, and dysmorphic features, including down-slanting palpebral fissures, a beaked nose, broad thumbs, and halluces. Mutations in the gene encoding the CREB-binding protein gene (CREBBP, also known as CBP) on chromosome 16p13.3 were identified in 1995. Recently, we developed a mutation analysis protocol using denaturing high-performance liquid chromatography (DHPLC) and identified heterozygous CREBBP mutations in 12 of 21 RTS patients. To test whether exonic deletions represent a common pathogenic mechanism, we assessed the copy number of all the coding exons using a recently developed method, the multiplex PCR/liquid chromatography assay (MP/LC). By using MP/LC, we performed screening for CREBBP exonic deletions among 25 RTS patients in whom no point mutations or small insertions/deletions were identified by DHPLC screening. We identified four classic RTS patients with deletions encompassing multiple exons (14-16, 5-31, 1-16, and 4-26). We conclude that large deletions including several exons are a relatively frequent cause of RTS, and that MP/LC is an effective method for detecting these deletions.

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.

Shwachman-Diamond syndrome (SDS; OMIM 260400) is an autosomal recessive disorder characterized by exocrine pancreatic insufficiency, bone marrow dysfunction and metaphyseal chondrodysplasia. SDS is caused by mutations in SBDS, an uncharacterized gene. A previous study in SDS patients largely of European ancestry found that most SBDS mutations occurred within a approximately 240-bp region of exon 2 and resulted from gene conversion due to recombination with a pseudogene, SBDSP. It is unknown, however, whether these findings are applicable to other ethnic groups. To address this question, we examined SBDS mutations in six Japanese families with SDS by direct sequencing. We identified compound heterozygous mutations in four families: two were recurrent (96-97insA, 258+2T>C), and three were novel [292-295delAAAG, (183-184TA>CT +201A>G), (141C>T+183-184TA>CT+201A>G)] mutations. Most of these mutations also appear to result from gene conversion, but the conversion events occurred at various sites between intron 1 and exon 3. Thus, gene conversion mutations in SBDS are common to different ethnic groups, but they are not confined to a limited region of the gene.

We describe a de novo balanced reciprocal translocation between the long arms of chromosomes 5 and 8 [46,XX,t(5;8)(q35;q24.1)] in a 15-month-old girl with a typical Sotos syndrome phenotype. Involvement of the 5q35 region was previously reported (Maroun et al. [1994: Am J Med Genet 50:291-293]) as one of translocation breakpoints in the present patient. We suggest that the gene responsible for Sotos syndrome is located to a distal long-arm region of chromosome 5.