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The pontocerebellar hypoplasias PCH are a group of earlyonset, autosomal recessive disorders resulting in abnormal growth and function of the brainstem and cerebellum. PCH type 2 PCH2 is characterized by respiratory and feeding difficulties at birth, extrapyramidal dyskinesia, severe developmental impairment, progressive microcephaly and frequent death in childhood. Neuropathologic findings include diffuse cerebral gliosis with white matter changes, hypoplastic pons with depletion of neurons in the pontine nuclei, hypoplastic cerebellar hemispheres due to short cerebellar folia with poor branching, segmental loss of dentate, inferior olivary, and ventral pontine nuclei, and near absence of transverse pontine fibers with preservation of long fiber tracts and spinal anterior horn cells. On brain imaging, the cerebellar hemispheres appear very flat, and are more severely involved than the vermis. Most patients with PCH2 have mutations in TSEN54, with occasional mutations found in TSEN34or TSEN2, genes that encode subunits of tRNA splicing endonuclease. Although this is a congenital disorder of pontocerebellar dysgenesis with fetal onset of neurodegeneration and symptoms at birth, prenatal imaging is unreliable in diagnosing this disorder in utero. We report on IVF dizygous twins with detailed prenatal imaging that failed to reveal any cerebellar abnormalities. Direct sequence analysis of TSEN54showed homozygosity for c.919G>T, the common founder mutation in most PCH2 patients, and both parents were heterozygous for this mutation. We found no evidence of cerebellar dysgenesis on prenatal ultrasounds, but MRI tractography showed absence of pontine crossing fibers, a unique feature that might be useful for prenatal diagnosis of this condition. © 2010 WileyLiss, Inc.

Nonsyndromic craniosynostosis is multifactorial, and fetal head constraint has been hypothesized as one factor thought to play a role. Data from the National Birth Defects Prevention Study NBDPS, a large multisite case–control study of birth defects, were used to evaluate associations between four selected factors related to fetal constraint and craniosynostosis: plurality twins or higher, macrosomia birth weight >4,000 g, postterm gestational age ≥42 weeks, and nulliparity no previous live births. Case infants n  675 had craniosynostosis documented either by radiographic evidence or by surgical intervention. Infants with a recognized or strongly suspected singlegene conditions or chromosomal abnormalities were excluded. Control infants n  5,958 had no major birth defects and were randomly selected from the same population as case infants. Logistic regression was used to estimate odds ratios for the association between these four factors and craniosynostosis, while adjusting for several covariates. We found that plurality and nulliparity were associated with a twofold increased risk for metopic craniosynostosis, and macrosomia had almost twice the risk of developing coronal craniosynostosis. Contrary to our hypothesis, prematurity and low birth weight were also associated with craniosynostosis. In conclusion, these four constraintrelated factors were not found to be associated with craniosynostosis when all suture types were combined, though some types of craniosynostosis were associated with individual constraintrelated factors. © 2010 WileyLiss, Inc.

Cleidocranial dysplasia (CCD) is a rare autosomal dominant skeletal dysplasia due to mutations causing haploinsufficiency of RUNX2, an osteoblast transcription factor specific for bone and cartilage. The classic form of CCD is characterized by delayed closure of the fontanels, hypoplastic or aplastic clavicles and dental anomalies. Clinical reports suggest that a subset of patients with CCD have skeletal changes which mimic hypophosphatasia (HPP). Mutations in RUNX2are detected in approximately 65% of cases of CCD, and microdeletions occur in 13%. We present clinical and radiological features in a 6‐year‐old child with severe CCD manifested by absence of the clavicles marked calvarial hypomineralization, osteoporosis and progressive kyphoscoliosis. HPP features included Bowdler spurs, severe osteopenia, and low alkaline phosphatase. Following negative mutation analysis of RUNX2, comparative genomic hybridization (CGH) microarray was performed. The result revealed a microdeletion in RUNX2, disrupting the C‐terminal part of the gene. © 2009 Wiley‐Liss, Inc.

Noonan syndrome NS is a genetically heterogeneous disorder caused most commonly by activating mutations in PTPN11. We report a patient with hypotonia, developmental delay and clinical features suggestive of NS. Highresolution chromosome analysis was normal, and sequence analyses of PTPN11, SOS1, KRAS, BRAF, RAF1, MEK, and MEK2were also normal. Array CGH revealed a single copy gain of 9 BAC clones at 12q24.11q24.21 8.98 Mb in size, which encompassed the PTPN11locus at 12q24.13 and was confirmed by FISH analysis. Shchelochkov et al. Shchelochkov et al. 2008; Am J Med Genet Part A 146A:1042–1048 reported a similar case and speculated that such duplications might account for 15–30 of NS cases with no detectable mutation in NS genes. We screened more than 250 NS cases without mutation in known NS diseasecausing genes by quantitative PCR, and none of these studies produced results in the duplicated range. We also explored the possibility that de novo changes affecting the untranslated region UTR of the PTPN11transcript might represent an alternative event involved in SHP2 enhanced expression. DHPLC analysis and direct sequencing of the entire 3′ UTR in 36 NS patients without mutation in known genes did not show any diseaseassociated variant. These findings indicate that duplications of PTPN11represent an uncommon cause of NS, and functionally relevant variations within the 3′UTR of the gene do not appear to play a major role in NS. However, recurrent observations of NS in individuals with duplications involving the PTPN11locus suggest that increased dosage of SHP2 may have dysregulating effects on intracellular signaling. © 2009 WileyLiss, Inc.

An international group of clinicians working in the field of dysmorphology has initiated the standardization of terms used to describe human morphology. The goals are to standardize these terms and reach consensus regarding their definitions. In this way, we will increase the utility of descriptions of the human phenotype and facilitate reliable comparisons of findings among patients. Discussions with other workers in dysmorphology and related fields, such as developmental biology and molecular genetics, will become more precise. Here we introduce the anatomy of the periorbital area and define and illustrate the terms that describe the major characteristics of the periorbital area. © 2009 WileyLiss, Inc.

Opitz and Kaveggia Opitz and Kaveggia 1974; Z Kinderheilk 117:1–18 reported on a family of five affected males with distinctive facial appearance, mental retardation, macrocephaly, imperforate anus and hypotonia. Risheg et al. Risheg et al. 2007; Nat Genet 39:451–453 identified an identical mutation p.R961W in MED12in six families with Opitz–Kaveggia syndrome, including a surviving affected man from the family reported in 1974. The previously defined behavior phenotype of hyperactivity, affability, and excessive talkativeness is very frequent in young boys with this mutation, along with socially oriented, attentionseeking behaviors. We present case studies of two older males with FG syndrome and the p.R961W mutation to illustrate how their behavior changes with age. We also characterize the behavior of eight additional individuals with FG syndrome and this recurrent mutation in MED12using the Vineland Adaptive Behavior Scales 2nd edition, the Reiss Profile of Fundamental Goals and Motivation Sensitivities, and the Achenbach Child Behavior Checklist. Males with this MED12mutation had deficits in communication skills compared to their socialization and daily living skills. In addition, they were at increased risk for maladaptive behavior, with a propensity towards aggression, anxiety, and inattention. Based on the behavior phenotype in 10 males with this recurrent MED12mutation, we offer specific recommendations and interventional strategies. Our findings reinforce the importance of testing for the p.R961W MED12mutation in males who are suspected of having developmental and behavioral problems with a clinical phenotype that is consistent with FG syndrome. © 2008 WileyLiss, Inc.

Useful and meaningful counseling following the discovery of a fetal loss or fetal anomalies requires an accurate diagnosis. In order to achieve this, our center utilized a multidisciplinary approach which included an ultrasonographer, perinatologist, genetic counselor, dysmorphologist, clinical geneticist, and pathologist. In this article, we report our experience with the analysis and evaluation of 534 cases seen between 1989 and 2000. In total, we were able to identify the cause of fetal loss in 369 cases (69%). In 98/369 cases (18.4%) the condition was attributed to a Mendelian process and in 78 (14.6%), to chromosomal abnormalities. The overall average maternal age was 31.6 years, the maternal age in cases of chromosomal abnormality was slightly higher (33.3 years). Our findings described below reiterate the clinical usefulness of a team specifically trained in the approach to fetal loss and/or fetal anomalies. © 2007 Wiley‐Liss, Inc.

Wormian bones are accessory bones that occur within cranial suture and fontanelles, most commonly within the posterior sutures. They occur more frequently in disorders that have reduced cranial ossification, hypotonia or decreased movement, thereby resulting in deformational brachycephaly. The frequency and location of wormian bones varies with the type and severity of cranial deformation practiced by ancient cultures. We considered the hypothesis that the pathogenesis of wormian bones may be due to environmental variations in dural strain within open sutures and fontanelles. In order to explore this further, we measured the cephalic index (CI) in 20 purposefully deformed pre‐Columbian skulls: 10 from Chichen Itza, Mexico, and 10 from Ancon, Peru, as well as 20 anatomically normal skulls used for medical school anatomy classes. We tested for a direct correlation between the CI and the number of wormian bones in skulls with varying degrees of brachycephalic cranial deformation and found no significant correlation. When the CI was grouped into three categories (normal (CI < 81), brachycephalic (CI 81‐93), and severely brachycephalic (CI > 93)) there was a trend toward increasing number of wormian bones as the skull became more brachycephalic (P = 0.039). A second part or our study tabulated the frequency and location of large wormian bones (greater than 1 cm) in 3‐dimentional computerized tomography (3D‐CT) scans from 207 cases of craniosynostosis and compared these data with published data on 485 normal dry skulls from a manuscript on wormian bones by Parker in 1905. Among cases of craniosynostosis, large wormian bones were significantly more frequent (117 out of 207 3D‐CT scans) than in dry skulls (131 out of 485). There was a 3.5 greater odds of developing a wormian bone with premature suture closure (P < 0.001). Midline synostosis, specifically metopic or sagittal synostosis, has more wormian bones in the midline, whereas unilateral lambdoidal or coronal synostosis more often had wormian bones on the contralateral side. Taken together, these data suggest that wormian bones may arise as a consequence of mechanical factors that spread sutures apart and affect dural strain within sutures and fontanelles. © 2007 Wiley‐Liss, Inc.

Here, we report the neuroimaging findings and neurological changes in 17 unpublished patients with Macrocephaly–Capillary Malformation (M–CM). This syndrome has been traditionally known as Macrocephaly–Cutis Marmorata Telangiectatica Congenita (M–CMTC), but we explain why M–CM is a more accurate term for this overgrowth syndrome. We analyzed the 17 patients with available brain MRI or CT scans and compared their findings with features identified by a comprehensive review of published cases. White matter irregularities with increased signal on T2‐weighted images were commonly observed findings. A distinctive feature in more than half the patients was cerebellar tonsillar herniation associated with rapid brain growth and progressive crowding of the posterior fossa during infancy. In four such cases, we confirmed that the tonsillar herniation was an acquired event. Concurrently, with the development of these findings, ventriculomegaly (frequently obstructive) and dilated dural venous sinuses were observed in conjunction with prominent Virchow–Robin spaces in many of those in whom cerebellar tonsil herniation had developed. We postulate that this constellation of unusual features suggests a dynamic process of mechanical compromise in the posterior fossa, perhaps initiated by a rapidly growing cerebellum, which leads to congestion of the venous drainage with subsequently compromised cerebrospinal fluid reabsorption, all of which increases the posterior fossa pressure and leads to acquired tonsillar herniation. We make a distinction between congenital Chiari I malformation and acquired cerebellar tonsil herniation in this syndrome. We also observed numerous examples of abnormal cortical morphogenesis, including focal cortical dysplasia, polymicrogyria which primarily involved the perisylvian and insular regions, and cerebral and/or cerebellar asymmetric overgrowth. Other findings included a high frequency of cavum septum pellucidum or vergae, thickened corpus callosum, prominent optic nerve sheaths and a single case of venous sinus thrombosis. One patient was found to have a frontal perifalcine mass resembling a meningioma at age 5 years. This is the second apparent occurrence of this specific tumor in M–CM. © 2007 Wiley‐Liss, Inc.

We report on six cases from four families with the newly described skeletal disorder diaphanospondylodysostosis (DSD). The characteristic radiographic findings included abnormal ossification of vertebral bodies, posterior rib gaps, missing ribs, and a downward tilt of the pubic rami, but normal long bones. The typical facial features of DSD cases were ocular hypertelorism, a short nose, depressed nasal bridge, and low set ears. Other distinctive findings included a short neck with bell‐shaped thorax, and nephroblastomatosis. A history of consanguinity and affected siblings with unaffected parents supports autosomal recessive inheritance. Skeletal histology showed incomplete ossification of the ribs, vertebral bodies, and sacrum as well as incomplete formation of intervertebral discs. The posterior ribs were comprised of bone with intervening cartilage interrupted by dense fibrous tissue and skeletal muscle fascicles. These findings suggest abnormal development and differentiation of the paraxial mesoderm. Because of phenotypic similarities of DSD to Pax1 and Meox1 deficient mice, we sequenced genomic DNA from three unrelated DSD cases. No mutations were identified in the PAX1 and MEOX1 exons or flanking intronic sequences, excluding them as likely causative genes. © 2007 Wiley‐Liss, Inc.

Sex chromosomal aneuploidy is the most common disorder of sex chromosomes in humans, with an incidence of 1 in 400 newborns. The addition of more than one extra X and/or Y chromosome to a normal male karyotype is less frequent and has its own distinctive physical and behavioral profile. This study examines the behavioral similarities and differences in individuals with 48,XXYY compared to 48,XXXY and 49,XXXXY. The participants include 11 males with 48,XXYY and 13 males with 48,XXXY and 49,XXXXY. Using the Vineland Adaptive Behavior, the Achenbach Child Behavior Checklist, and the Reiss Personality Profiles, parents are asked to characterize the behavior and personality of their boys with sex chromosome tetrasomy and pentasomy. Males with 48,XXYY have higher overall adaptive scales in daily living skills, socialization, and communication compared to males with 48,XXXY and 49,XXXXY. Both groups are at risk for maladaptive behavior, although 48,XXYY males are at a higher risk for internalizing and externalizing symptoms. 48,XXXY and 49,XXXXY function at a lower cognitive level and their behavior is often immature for their chronological age. Both groups display interests in helping others, but have a low tolerance for being rejected or teased. Specific recommendations and interventional strategies are provided for individuals with 48,XXYY, 48,XXXY, and 49,XXXXY. © 2007 Wiley‐Liss, Inc.

Currarino syndrome consists of autosomal dominant hereditary sacral dysgenesis that is caused by mutations of the HOX gene, HLXB9. Sacral malformation, presacral mass, and anorectal malformations comprise the classic triad, but other common symptoms and malformations include neonatal‐onset bowel obstruction, chronic constipation, recurrent perianal sepsis, renal/urinary tract anomalies, female internal genital anomalies, tethered spinal cord, and anterior meningocele. Up to 33% of patients are asymptomatic. There is marked inter‐ and intrafamilial variability in expression, and no genotype/phenotype correlations have been identified. To date, 32 different mutations have been identified in HLXB9: all nine missense mutations were found in the homeodomain, while the others were nonsense, frameshift, splice site mutations, or heterozygous whole‐gene deletions. We report a four‐generation family with Currarino syndrome varying in severity from very mild to full expression of the Currarino triad. They were found to carry a previously unreported nonsense mutation, E283X, absent in tested asymptomatic first‐degree relatives. This family provides additional information on the degree of intrafamilial variability associated with HLXB9 mutations. © 2006 Wiley‐Liss, Inc.

Bosma et al. [1981] delineated a syndrome affecting two unrelated males with severe hypoplasia of the nose and eyes, palatal abnormalities, deficient taste and smell, inguinal hernias, hypogonadotropic hypogonadism with cryptorchidism, and normal intelligence. Other patients with this syndrome have been reported as cases of arhinia with associated defects. During embryonic development, the nasal placodes form 28 days after conception shortly after the optic vesicles makes contact with the overlying surface ectoderm at 26–27 days, and both layers invaginate to form the eyes between 34 and 44 days. Mice with homozygous mutations of Pax6, manifest underdevelopment of ocular and nasal structures, and a network of developmentally regulated genes function downstream of Pax6 to form nasal, ocular, and pituitary structures. These genes represent candidate genes for this disorder, and familial recurrence of Bosma syndrome has been reported to occur. This report describes two sporadic unrelated cases of this rare syndrome and briefly reviews the findings in previously reported cases. © 2005 Wiley‐Liss, Inc.

CHARGE syndrome was independently reported by Hall [(1979): J Pediatr 95:395–398] and Hittner et al. [(1979): J Pediatr Ophthalmol Strabismus 16:122–128] and was initially considered to be a non‐random association between distinct multiple congenital anomalies. It is now considered to be a recognizable syndrome with well‐characterized diagnostic criteria and a genetic pathogenesis. We report on a 33‐year‐old adult male with CHARGE syndrome, with emphasis on the unique medical, behavioral, and psychological issues faced in adulthood. Characteristic facial and ear abnormalities were obvious in early childhood, and bilateral retinal colobomata, left choanal atresia, right congenital hip dislocation, and hypogonadism were diagnosed during the first year. Walking was delayed due to vestibular problems, speech was impaired due to moderately severe hearing loss, and use of sign communication was limited. Choanal atresia was surgically corrected in infancy, and atrial septal defect, ventricular septal defect, and patent ductus arteriosus were surgically corrected in childhood. Undescended testes were removed in adolescence, and gallstones were removed in early adulthood. Puberty was delayed until hormone replacement therapy began at 15 years. Behavioral disturbances and anxiety persisted throughout childhood, adolescence, and into adulthood, often resulting from communication challenges. At 33 years of age, he lives independently in a supervised group home, receives regular eye check‐ups and is being monitored for severely reduced bone density. © 2005 Wiley‐Liss, Inc.

CHARGE syndrome is a well‐characterized clinical diagnosis with recent data supporting a genetic etiology. A 3‐year national surveillance coordinated by the Canadian Pediatric Surveillance Program (CPSP) was started in September 2001. Physicians notified the CPSP if they had cared for individuals with CHARGE syndrome within their practice, and then completed a detailed reporting form. To date, there are 77 confirmed cases of CHARGE syndrome. The highest provincial prevalence of CHARGE syndrome in Canada was estimated at 1 in 8,500 live births. Subgroups of cases with particular clusters of anomalies were identified. In older individuals, bilateral posterior choanal atresia (BPCA) was predictive of the presence of the three other major criteria and of aortic arch anomalies. Individuals with CHARGE syndrome who demonstrated a less extensive phenotype (≤3 major criteria) were more likely to present with minor cardiovascular malformations, including small atrial or ventricular septal defects (VSD) or patent ductus arteriosus (PDA). A significant cause of morbidity was severe feeding difficulty, including problems with chewing, swallowing, and gastroesophageal reflux, which were prevalent throughout childhood. Infant mortality is high in individuals with CHARGE syndrome. However, life expectancy has improved for those surviving their first year. Increased mortality was associated with distinct cardiovascular malformations or ventriculomegaly combined with brainstem or cerebellar anomalies. From this study, revised diagnostic criteria are proposed for infants, children, and adolescents to help identify a group of individuals who represent CHARGE syndrome with more of the classical features as apposed to the boarder association. © 2005 Wiley‐Liss, Inc.

CHARGE syndrome, or Hall–Hitner syndrome (HHS), has been delineated as a common syndrome that includes coloboma, choanal atresia, cranial nerve dysfunction (particularly asymmetric facial palsy and neurogenic swallowing problems), characteristic ear abnormalities, deafness with hypoplasia of the cochlea and semicircular canals, genital hypoplasia, and variable heart defects, orofacial clefting, tracheo‐esophageal fistula, renal anomalies, thymic/parathyroid hypoplasia, spine anomalies, short broad neck with sloping shoulders, and characteristic facial features. We conducted behavioral and personality assessments in 14 boys with HHS syndrome aged 6–21 years, and compared their characteristics with similar data from 20 age‐matched boys with Down syndrome (DS), 17 boys with Prader–Willi syndrome (PWS), and 16 boys with Williams syndrome (WS). We used the Reiss Profile of Fundamental Goals and Motivation Sensitivities, the Achenbach Child Behavior Checklist (CBCL), and the Aberrant Behavior Checklist (ABC). All 14 boys with HHS were legally deaf, and 10 of the 14 were also legally blind. In comparison these other syndromes, boys with HHS had behavior that resembled autistic spectrum disorder. They were socially withdrawn, lacked interest in social contact, and manifested reduced seeking of attention from others, with hyperactivity and a need to maintain order. Though the boys with HHS showed decreased social interaction, they were not as socially impaired as in classic autism. Their language was delayed due to dual sensory impairment, cranial nerve deficits, and chronic medical problems, but their language style was not abnormal (no echolalia or jargon, no scripted phrases, and no pronoun reversal). Boys with HSS appeared frustrated, but they were not aggressive, or at risk for delinquency, manifesting few stereotypic behaviors or unusual preoccupations. They did not have a restricted repertoire of activities and interests. Their behavioral features appeared to be due to dual sensory impairment affecting hearing and vision, rather than to primary autistic spectrum disorder, but successful remediation requires similar educational interventions, which are discussed herein. © 2005 Wiley‐Liss, Inc.

Kabuki syndrome is a multiple congenital anomaly/mental retardation syndrome. This study of Kabuki syndrome had two objectives. The first was to further describe the syndrome features. In order to do so, clinical geneticists were asked to submit cases—providing clinical photographs and completing a phenotype questionnaire for individuals in whom they felt the diagnosis of Kabuki syndrome was secure. All submitted cases were reviewed by four diagnosticians familiar with Kabuki syndrome. The diagnosis was agreed upon in 48 previously unpublished individuals. Our data on these 48 individuals show that Kabuki syndrome variably affects the development and function of many organ systems. The second objective of the study was to explore possible etiological clues found in our data and from review of the literature. We discuss advanced paternal age, cytogenetic abnormalities, and familial cases, and explore syndromes with potentially informative overlapping features. We find support for a genetic etiology, with a probable autosomal dominant mode of inheritance, and speculate that there is involvement of the interferon regulatory factor 6 (IRF6) gene pathway. Very recently, a microduplication of 8p has been described in multiple affected individuals, the proportion of individuals with the duplication is yet to be determined. © 2004 Wiley‐Liss, Inc.

Children born with the findings of microcephaly, cataracts and microcornea can result not only from a prenatal viral infection, but also from an autosomal recessive Mendelian disorders. We present three pairs of affected siblings with MICRO syndrome, who were born with congenital microcephaly, microcornea, and cataracts. MICRO syndrome is an autosomal recessive syndrome consisting of congenital microcephaly, cortical dysplasia, microcornea, cataracts, optic atrophy, severe mental retardation, hypotonic diplegia, and hypogenitalism. At birth, MICRO syndrome resembles Cerebro‐Oculo‐Facio‐Skeletal (COFS) syndrome, but it differs in the lack of the rapidly progressive neurologic features leading to severe brain atrophy with calcifications. Patients with MICRO syndrome manifest frontal cortical dysplasia, hypoplasia of the corpus callosum, cortical blindness with optic atrophy, profound mental retardation, and progressive joint contractures with growth failure. COFS syndrome shares also many clinical and cellular similarities with Cockayne syndrome (CS), and cultured cells in both conditions demonstrate hypersensitivity to ultraviolet (UV) radiation due to impaired nucleotide excision repair (NER). NER studies in cultured fibroblasts from MICRO patients give normal results, so MICRO syndrome should be considered in children with features resembling COFS syndrome and CS, but who have normal NER. MICRO should be distinguished from other similar clinical disorders with normal NER by the presence of significant visual impairment and cortical blindness despite early surgery for congenital cataracts, frontal polymicrogyria, thin corpus callosum, and cortical atrophy by MRI. © 2004 Wiley‐Liss, Inc.

No abstract

In 1983, Johnson et al. described 16 related individuals with alopecia, anosmia or hyposmia, conductive hearing loss, microtia and/or atresia of the external auditory canal, and hypogonadotrophic hypogonadism inherited in an autosomal dominant pattern. Other less constant manifestations included facial asymmetry, mental retardation, congenital heart defect, cleft palate, and choanal stenosis. An isolated case was reported later (Johnston et al. [1987: Am J Med Genet 26: 925–927]) and thereafter an affected mother and son (Hennekam and Holtus [1993: Am J Med Genet 47: 714–716]). We describe an additional unrelated female patient with features resembling those of the previously reported cases. She presented with intrauterine growth deficiency, microcephaly, alopecia, bilateral microtia with canal atresia, conductive hearing loss, partial left facial palsy, posterior cleft palate, left choanal stenosis, tetralogy of Fallot, developmental delay, and right thumb polydactyly. Because the phenotypic abnormalities in this syndrome affect the brain, facial structures, ectoderm and its derivatives, outflow tract of the heart, and Rathke's pouch derivatives, this has suggested to previous authors etiologic involvement of the ectoderm and neuroectoderm of the first and second branchial arches, Rathke's pouch, and the diencephalon. Microtia with conductive hearing loss differentiates the condition from other ectodermal dysplasias. In the initial report, females appeared somewhat less affected than males, and there was male-to-male transmission. The mother of our patient manifests subtle features, which suggest she may be a mildly affected female. Additionally, there is a family history of early-onset alopecia in the maternal grandfather's relatives. © 2003 Wiley-Liss, Inc.

CHARGE syndrome is a distinctive subgroup within the more heterogeneous group of patients with CHARGE association. While significant progress has been made in the clinical delineation of this syndrome, the molecular basis of the disorder remains unknown. Based on the complex phenotype, some overlap with DiGeorge/velocardiofacial syndrome (DGS/VCFS), and its estimated population incidence, we hypothesized that CHARGE syndrome could be caused by an unidentified genomic microdeletion. In order to address this hypothesis, we carried out a genome-wide screen for loss of expected heterozygosity using 811 microsatellite markers in ten CHARGE syndrome subjects and their unaffected parents. Eight markers gave results suggestive of failure to inherit one parental allele. These loci were tested with fluorescence in situ hybridization (FISH), but none showed evidence of deletion. This screen sets upper limits on the length of a CHARGE-related microdeletion, should that be the genetic mechanism underlying the phenotype. © 2003 Wiley-Liss, Inc.

We describe two Hispanic brothers born to unrelated parents with van den Ende–Gupta syndrome (VDEGS), a distinctive combination of characteristic dysmorphic features, skeletal abnormalities, and cerebellar hyperplasia. This syndrome was previously delineated by van den Ende et al. [1992: Am J Med Genet 42:467–469] and Gupta et al. [1995: J Med Genet 32:809–812], with additional reports by Phadke et al. [1998: Am J Med Genet 77:16–18] and Bistritzer et al. [1993: Clin Genet 44:15–19]. This is the fifth report of VDEGS, which is characterized by blepharophimosis, narrow nose with hypoplastic alae nasi, hypoplastic maxilla, everted lower lip, slender and elongated hands and feet, arachnodactyly, self-limiting joint contractures, and distinctive skeletal findings. This report of affected siblings, and a previous report of double second cousins born to consanguineous parents [Bistritzer et al. [1993: Clin Genet 44:15–19]], suggests autosomal recessive inheritance. This brings to eight, the total number of reported cases, derived from six families, three of which are consanguineous. It is important to distinguish VDEGS from Marden–Walker syndrome (MWS) since both syndromes include blepharophimosis, arachnodactyly, and congenital contractures. Both syndromes are inherited in an autosomal recessive fashion, but VDEGS lacks severe mental retardation, serious brain malformations, microcephaly, failure to thrive, and severe joint limitation, which are consistently present in MWS. Of particular importance, MWS may be associated with cerebellar malformations such as Dandy-Walker malformation, while the brothers reported herein with VDEGS both demonstrated distinctive cerebellar enlargement, a new finding for this disorder. While, congenital contractures with arachnodactyly are features commonly seen in several other delineated syndromes, such as congenital contractural arachnodactyly (CCA) syndrome, characteristic facial features (blepharophimosis, narrow nose with ocular hypertelorism, prominent ears, and everted lower lip), distinguish VDEGS from other syndromes associated with CCA, including CCA. © 2003 Wiley-Liss, Inc.

CDMP-1, a cartilage-specific member of the TGFß superfamily of secreted signaling molecules, plays a key role in chondrogenesis, growth and patterning of the developing vertebrate skeleton. Homozygous CDMP-1 mutations cause Hunter-Thompson and Grebe types of acromesomelic chondrodysplasia and DuPan syndrome in humans, as well as brachypodism in mice, while heterozygous mutations cause brachydactyly type C (BDC). We present clinical and radiographic data from three unrelated families in which 12 members share the same heterozygous CDMP-1 mutation, an insertion (insG206), resulting in a frameshift predicted to cause functional haploinsufficiency. Although eight mutation carriers display BDC, four have normal hands and feet, confirming nonpenetrance of BDC with CDMP-1 mutations. In addition, several carriers have other skeletal abnormalities, including severe bilateral vertical talus (in two), developmental hip dysplasia (in one), and short stature (in two, who are otherwise unaffected). Premature vertebral end-plate disease was observed in four mutation carriers and was associated with spondylolysis and spondylolisthesis in three of these. Axial skeletal involvement has not been previously reported in association with CDMP-1 mutations. This finding is consistent with CDMP-1 expression in human hypertrophic chondrocytes, which are present in the ring epiphyses of vertebral end plates. Phenotypic variation in BDC has previously been attributed either to locus heterogeneity or to the varied functional effects of different CDMP-1 mutations. The remarkable range of phenotypes caused by this identical CDMP-1 mutation in these families emphasizes the crucial role of genetic background, stochastic variation and/or environmental factors in modifying the observed phenotype. Our findings illustrate that nonpenetrance for the typical features of BDC can be appreciable and that atypical skeletal features that have been reported in some patients with BDC (i.e., clubfoot, short stature, spondylolysis) may also result from CDMP-1 mutation. © 2002 Wiley-Liss, Inc.

Dolichospondylic dysplasia (DD) is a rare skeletal dysplasia primarily characterized by tall vertebral bodies and disproportionate short stature. Radiographic manifestations include tall vertebral bodies and gracile bones of the hands. Patients usually have eye and ear findings in addition to borderline mental retardation; however, tall vertebral bodies and slender tubular bones are also seen in the 3-M syndrome. Patients with the 3-M syndrome have a characteristic face with a triangular shape, frontal bossing, a flattened malar region, full eyebrows, a short nose with a bulbous tip, upturned nares, and full lips. We present two unrelated patients who share a distinct phenotype and have tall vertebral bodies, overtubulation of long bones, and short tubular bones of the hands and feet. We discuss the overlapping and distinguishing features between DD and the 3-M syndrome. Patient 1 was a 13-year-old female, and patient 2 was an unrelated adult female. These patients had normocephaly and short stature. They shared a common phenotype consisting of mild malar hypoplasia, a narrowed nasal body with a fleshy tip, full lips, and normal intelligence. In addition, they showed mild hand and foot abnormalities. These two patients lack many of the typical clinical features of both DD and the 3-M syndrome. They share a common phenotype and likely represent a distinct disorder. The spectrum of disorders with tall vertebral bodies as a key feature may include different entities that may be further defined with the characterization of the molecular defect(s). © 2002 Wiley-Liss, Inc.

Growth/differentiation factor-5 (GDF5), also known as cartilage-derived morphogenetic protein-1 (CDMP-1), is a secreted signaling molecule that participates in skeletal morphogenesis. Heterozygous mutations in GDF5, which maps to human chromosome 20, occur in individuals with autosomal dominant brachydactyly type C (BDC). Here we show that BDC is locus homogeneous by reporting a GDF5 frameshift mutation segregating with the phenotype in a family whose trait was initially thought to map to human chromosome 12. We also describe heterozygous mutations in nine additional probands/families with BDC and show nonpenetrance in a mutation carrier. Finally, we show that mutant GDF5 polypeptides containing missense mutations in their active domains do not efficiently form disulfide-linked dimers when expressed in vitro. These data support the hypothesis that BDC results from functional haploinsufficiency for GDF5. © 2002 Wiley-Liss, Inc.

No abstract.

A unique type of craniofacial dysostosis, Crouzon syndrome with acanthosis nigricans (CAN), has been attributed to a specific substitution (Ala391Glu) in the fibroblast growth factor receptor 3 (FGFR3) gene. At birth, individuals with this disorder have craniosynostosis, ocular proptosis, midface hypoplasia, choanal atresia, hydrocephalus, and they experience the onset of acanthosis nigricans during childhood. We report three cases and compare the clinical characteristics of our cases with the previously reported cases of this disorder. Since the Ala391Glu substitution in FGFR3 is close to the substitutions in the transmembrane domain that result in achondroplasia, we carefully reviewed the skeletal findings in six patients. We identified subtle radiographic findings of achondroplasia in all six cases including narrow sacrosciatic notches, short vertebral bodies, lack of the normal increase in interpediculate distance from the upper lumbar vertebrae caudally, and broad, short metacarpals and phalanges. Even before acanthosis nigricans appears, the presence of choanal atresia and hydrocephalus in an individual with features of Crouzon syndrome should suggest the diagnosis of CAN, and subtle skeletal findings can lend further support to this diagnosis. © 2001 Wiley-Liss, Inc.

Mosaic trisomy 7 is a rare condition that can be seen in individuals with Blaschkolinear skin pigmentary variation, somatic asymmetry, and variable other clinical anomalies. In any patient presenting with Blaschkolinear skin pigmentary variation, varying degrees of asymmetrical growth disturbance, developmental delay, and a normal lymphocytic karyotype, chromosomal mosaicism may be present. To rule out tissue-specific or occult chromosomal mosaicism, it is recommended to culture and karyotype skin fibroblasts, since lymphocyte cell lines may not demonstrate the abnormal cell line. Early diagnosis is of paramount importance, since early physical, occupational, and speech/language therapy can greatly improve the developmental outcome of these patients. We report on a fourth patient with trisomy 7 mosaicism in whom early diagnosis and developmental therapy contributed to an improved developmental outcome when compared with patients in previous reports. Early intervention can greatly benefit patients with this diagnosis, especially in minimizing the aggressive behavior associated with communication difficulties. Our patient has milder manifestations than the previously reported patients with no seizure activity or asymmetry and fewer cells with trisomy 7. Am. J. Med. Genet. 95:281–284, 2000. © 2000 Wiley-Liss, Inc.

Based on cases that had been excluded from a previous clinical study of Sotos syndrome, Cole and Hughes [1991: Am J Med Genet 41:115–124] reported a new syndrome associated with marked obesity, occasional delayed bone age, distinctive facial anomalies, mental retardation, and progressive postnatal macrocephaly in the context of autosomal dominant familial macrocephaly. Subsequently, Stevenson et al. [1997: Lancet 349:1744–1745] emphasized the association of progressive postnatal macrocephaly with autism, and they suggested that this might comprise a recognizable autism syndrome. We report two additional patients with Cole-Hughes syndrome and associated autistic characteristics with attention deficit hyperactivity disorder. These patients seem to manifest a distinctive behavioral phenotype associated with Cole-Hughes syndrome and they manifest a distinct subgroup of persons with autism that may ultimately shed light on the pathogenesis of this disorder. Am. J. Med. Genet. 94:149–152, 2000. © 2000 Wiley-Liss, Inc.

FG syndrome is a rare X-linked recessive form of mental retardation, first described by Opitz and Kaveggia in 1974. Based on over 50 reported cases, FG syndrome is associated with agenesis of the corpus callosum, minor facial anomalies (high, broad forehead with frontal cowlick, ocular hypertelorism, down-slanted palpebral fissures, and small cupped auricles), relative macrocephaly, broad thumbs and halluces, and prominent fetal fingertip pads. Affected individuals manifest neonatal hypotonia and severe constipation, which usually resolves during mid-childhood. The hypotonia with joint hyperlaxity evolves into spasticity with joint contractures in later life. Affability, hyperactivity, and excessive talkativeness are noted frequently in patients with FG syndrome. Recently, we described three additional families (six additional patients) with FG syndrome who support the localization of a gene for the FG syndrome in chromosome region Xq12-q21 [Graham JM Jr, Tackels D, Dibbern K, Superneau D, Rodgers C, Corning K, Schwartz CE. 1998. Am J Med Genet 80:145–156.]. Using these same families and one additional sporadic case of FG syndrome, we compared behavioral and personality characteristics of 6 FG boys with other boys with syndromic and nonsyndromic mental retardation: eight with Down syndrome, seven with Prader-Willi syndrome, eight with nonspecific mental retardation, and 13 with Williams syndrome. Using the Vineland Adaptive Behavior Scales, the Reiss Personality Profiles, and the Achenbach Child Behavior Checklist, parents were asked to characterize the behavior and personality of their boys from ages 4 to 10 years. When compared with Williams syndrome, the FG boys had fewer internalizing behaviors and were significantly less anxious and withdrawn but had similar socially oriented, attention-seeking behaviors. On the Reiss Profile, FG boys were also quite similar to Williams syndrome boys. On the Vineland Scales, FG boys demonstrated significant relative strengths in their socialization skills, consistent with their personality, tending to confirm previous descriptions of their personalities. Am. J. Med. Genet. 85:470–475, 1999. © 1999 Wiley-Liss, Inc.

Proteus syndrome is a complex disorder comprising malformations and overgrowth of multiple tissues. The disorder is highly variable and appears to affect patients in a mosaic manner. This intrinsic variability has led to diagnostic confusion associated with a dearth of longitudinal data on the natural history of Proteus syndrome. To clarify some of these issues, a workshop on Proteus syndrome was held in March 1998 at the National Institutes of Health, and participants developed recommendations for diagnostic criteria, differential diagnosis, and guidelines for the evaluation of patients. This is a review of those recommendations. Am. J. Med. Genet. 84:389–395, 1999. © 1999 Wiley-Liss, Inc.

Lissencephaly is a brain malformation characterized by absence of gyral formation, resulting in a smooth brain surface. Histologic study shows severe anomalies of cerebral cortical development. Several lissencephaly syndromes have been described. Here we report a familial syndrome of lissencephaly, cleft palate, diffuse agyria, and severe cerebellar hypoplasia. Microscopic examination of the abnormally thick cerebral cortex showed absence of cortical layering, with preservation of the pia-glial barrier. This is the first report of recurrent lissencephaly with cleft palate and severe cerebellar hypoplasia in which these unique neuropathology findings are described. Autosomal recessive inheritance is suggested by recurrence in sibs within the same family, but germ cell mosaicism for a dominant mutation is not excluded. Am. J. Med. Genet. 87:440–445, 1999. © 1999 Wiley-Liss, Inc.