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We review the cardiac abnormalities in 94 patients (27 new, 67 literature) with Costello syndrome, an increasingly recognized syndrome consisting of increased birth weight, postnatal growth retardation, and distinctive facial, skin, and musculoskeletal features (MIM 218040). A cardiac abnormality was found in 59 (63%) patients, with each of three categories occurring in approximately one-third of patients. A cardiovascular malformation (CVM) was noted in 30%, typically pulmonic stenosis (46% of those with a CVM). Cardiac hypertrophy was reported in 34%, which involved the left ventricle in 50% and was usually consistent with classic hypertrophic cardiomyopathy (HCM). A variety of rhythm disturbances were reported in 33%. Most (74%) were atrial tachycardia that was reported as supraventricular, chaotic, multifocal, or ectopic. Of 31 patients with a rhythm abnormality, 22 (68%) had an additional abnormality, i.e., CVM (4), cardiac hypertrophy (12), or both (6). Nine patients had isolated dysrhythmia, five (56%) of whom died. All of the 12 (13%) patients who died had a cardiac abnormality. One patient died of embryonal rhabdomyosarcoma, but in the remainder, a cardiac cause of death could not be disproved. All patients with Costello syndrome need a baseline cardiology evaluation with echocardiography and Holter monitoring. Additional prospective evaluations, even in patients without apparent cardiac abnormalities, would be prudent, although data are insufficient to propose a specific schedule., (Copyright 2002 Wiley-Liss, Inc.)

The SHOX (short-stature homeobox-containing) gene encodes isoforms of a homeodomain transcription factor important in human limb development. SHOX haploinsufficiency has been implicated in three human growth disorders: Turner syndrome, idiopathic short stature, and Leri-Weill dyschondrosteosis. Langer mesomelic dysplasia is thought to be the homozygous form of dyschondrosteosis. However, complete SHOX deficiency has not been demonstrated for any postnatal patient with the classic Langer phenotype. We studied four adults and one child with Langer mesomelic dysplasia. SHOX abnormalities were detected in all five probands. One was a homozygote or hemizygote and two were compound heterozygotes. The homozygous or hemizygous mutation was in exon 6a, implying that the SHOXa isoform is essential for normal skeletal development. These findings confirm clinical inferences that Langer mesomelic dysplasia is the homozygous form of Leri-Weill dyschondrosteosis and add to our understanding of genotype/phenotype relationships in SHOX deficiency disorders., (Copyright 2002 Wiley-Liss, Inc.)

We report five new cases of rhabdomyosarcoma (RMS) in Costello syndrome. These cases, combined with those previously reported, increase the number of solid tumors to 17 (10 RMSs, 3 neuroblastomas, 2 bladder carcinomas, 1 vestibular schwannoma, 1 epithelioma), in at least 100 known Costello syndrome patients. Despite possible ascertainment bias, and the incomplete identification of all Costello syndrome patients, the tumor frequency could be as high as 17%. This is comparable to the 7-21% frequency of solid tumors in Beckwith-Wiedemann syndrome (BWS), and may justify tumor screening. Based on the recommendations for screening BWS patients, we propose a screening protocol consisting of ultrasound examination of the abdomen and pelvis every 3-6 months until age 8-10 years for RMS and abdominal neuroblastoma; urine catecholamine metabolite analysis every 6-12 months until age 5 years for neuroblastoma; and urinalysis for hematuria annually for bladder carcinoma after age 10 years. These recommendations may need to be modified, as new information becomes available. Potential criticism of the tumor screening protocol concerns the lack of evidence for improved outcome, and possible overestimation of the tumor risk. The ability of RMSs to occur at various sites complicates tumor screening, but 8 of the 10 RMSs in Costello syndrome patients originated from the abdomen, pelvis and urogenital area. Prior diagnosis of Costello syndrome is a prerequisite for the implementation of any screening protocol. The diagnosis of Costello syndrome should also be considered in individuals with RMS and physical findings suggestive of Costello syndrome., (Copyright 2002 Wiley-Liss, Inc.)

We present a boy followed from age 5-13 years who is the fifth reported case of ter Haar syndrome. This is a recently-named entity comprising congenital glaucoma, hypertelorism, congenital heart defects and kyphoscoliosis, skeletal dysplasia, and developmental delay. These patients were originally thought to have an autosomal-recessive form of Melnick-Needles syndrome, and were only identified as having a distinct syndrome with the report of the fourth case. Probable autosomal-recessive inheritance is based on consanguinity in 4 of 5 cases. Ocular, cardiac, and craniofacial findings distinguish ter Haar syndrome as a distinct entity. Our patient is the longest survivor at present, suggesting that there is heterogeneity in this syndrome or, alternatively, that aggressive therapy of the congenital heart defects has significant effect.

One female and two male patients with multiple lateral meningoceles are presented. They do not have neurofibromatosis or Marfan syndrome and share findings with the two previously described patients with multiple lateral meningoceles. The original report by Lehman et al. [1977: J Pediatr 90:49-54] was titled "familial osteosclerosis," because osteosclerosis was present in the proposita and her mother; the patient described by Philip et al. [1995: Clin Dysmorphol 4:347-351] also had increased bone density of the skull base and the sutures. Thickened calvaria were present in one of our patients; two had a prominent metopic suture. Other shared findings include multiple lateral meningoceles, Wormian bones, malar hypoplasia, downslanted palpebral fissures, a high narrow palate, and cryptorchidism in males. In addition, our patients showed ligamentous laxity, keloid formation, hypotonia, and developmental delay. A short umbilical cord was noted in two patients. One had a hypoplastic posterior arch of the atlas and an enlarged sella, as reported by Lehman et al. [1977]. Our patients appear to have the same syndrome as previously reported. We suggest it be called "lateral meningocele syndrome," because of this unique finding.

We describe a mother and son with multiple, non-progressive, congenital contractures, camptodactyly and absent flexion creases, expressionless face, blepharophimosis, microstomia, and short stature. Although these cases share similarities with the autosomal-recessive Schwartz-Jampel and Marden-Walker syndromes, they have a different mode of inheritance and lack myotonia, one of the most characteristic findings of the Schwartz-Jampel syndrome. Our cases most closely resemble those previously reported as distal arthrogryposis type IIb, although in our patients the proximal joints are severely affected and extraocular involvement is absent. Hearing loss is present in one and cleft palate in the other of our patients; these findings were previously described in arthrogryposis syndromes other than type IIb. We suggest extending the spectrum of distal arthrogryposis to include these manifestations, since there appears to be significantly overlap between the different syndromes.

Sponastrime dysplasia (SD) is a dwarfing autosomal recessive short-limb bone dysplasia. The diagnosis is established by a combination of clinical and radiological findings of which the radiological are the more specific. The current diagnostic criteria are ambiguous as demonstrated by the fact that, in our opinion, three of the five patients reported since the original article do not have this condition. Comparison of our five patients and the 9 published patients has led to development of more specific diagnostic criteria. Previously undescribed complications of this condition are subglottic stenosis and tracheo-broncho-malacia, developmental coxa vara, and avascular necrosis of the capital femoral epiphyses.

Standard curves developed for the general population cannot be used to assess the growth of an individual who has a condition that results in disproportionate short stature. For this reason, efforts have been made to develop growth curves specific for several of the chondrodysplasias. However, data concerning weight for height have been largely lacking, although they may be of particular importance for conditions such as achondroplasia, where there is some consensus that an increased prevalence of obesity is a particular problem. In this paper we provide standard weight for height curves for males and females with achondroplasia, and discuss the use of several indices which have been applied to the assessment of body fat in the general population.

Several pathogenetic factors, alone or in combination, may contribute to the increased frequency of respiratory complications in achondroplasia. It has been suggested that relatively small chest circumference sometimes may contribute. However, there are no published curves of chest circumference for age in achondroplasia with which to compare patients. Nor are there data relating chest circumference to overall size in achondroplasia. We present curves of chest circumference for males and females with achondroplasia from birth through age 7 years. Additional curves for chest circumference against height are also provided. Finally, we report some preliminary data regarding the possible association of chest size with respiratory signs and symptoms.

We describe a previously unrecognized syndrome in two unrelated patients with congenital cataracts, sensorineural deafness, distinctive facial appearance, skeletal changes, postnatal short stature, and mental retardation.

Aarskog-Scott syndrome was tentatively mapped to Xq13 on the basis of an X:8 translocation by Bawle et al. [Am J Med Genet 17:595-602, 1984]. A review of the cytogenetics and the use of molecular markers in that family have resulted in revision of the breakpoints of the translocation to Xp 11.2 and 8q11.21 [Glover et al., Hum Mol Genet 2:1717-1718, 1993]. Two families, including one of the two initial families with Aarskog-Scott syndrome [Scott, BD:OAS VII (6): 240-246, 1971], have participated in our study to evaluate the localization of the gene for Aarskog-Scott syndrome to the pericentromeric region of the X chromosome. Using a series of DNA probes, we have been able to confirm linkage to the X chromosome, with multipoint analysis indicating the most likely localization of the gene to be on the proximal short arm.

We present the results of ophthalmologic assessment in 10 patients with interstitial chromosome deletions of 17p11.2, otherwise known as the Smith-Magenis syndrome (SMS). The most common abnormalities noted were strabismus, Brushfield spots, high myopia, and retinal detachments. We have previously reported high myopia and retinal detachments in 6 patients with SMS (Finucane et al.: Am J Hum Genet 49:262A, 1991). We present additional details on these individuals, as well as findings in 4 newly reported patients. Ocular pathology appears to be very common in SMS, significantly contributing to disability in people with this syndrome. The combination of high myopia, self-injurious head-banging, aggression, and hyperactivity among these patients makes them particularly susceptible to retinal detachments. Detailed ophthalmologic assessment should be included in the clinical work-up and monitoring of all patients with SMS resulting from deletion 17p11.2.

Further delineation of a generalized bone dysplasia which we call spondylo-meta-epiphyseal dysplasia, short limb-abnormal calcification type is presented. This dwarfing condition has several serious complications, with the most common cause of death being spinal cord damage secondary to atlantoaxial instability. It is a heritable condition with an autosomal recessive mode of transmission. Radiologic diagnostic criteria are developed on the basis of studies in 8 patients with the oldest being between 4 and 5 years old. The condition is clinically and radiographically apparent neonatally or in early infancy, and it is probable that all or almost all affected individuals will come to medical attention in the age range screened by this study.

We describe a 14-year-old boy with physical and behavioral manifestations of the Smith-Magenis syndrome. Low level mosaicism (11%) for deletion 17p11.2 was found in peripheral blood lymphocytes. The deletion was also observed in 100% of metaphases examined from skin fibroblast cultures. We confirm that the Smith-Magenis syndrome is associated with a highly recognizable phenotype. Because evidence of the abnormal cell line may be minimal or absent in peripheral blood, fibroblast studies are indicated for patients in whom mosaicism for deletion 17p11.2 is suspected clinically.

We present 2 unrelated children with a distinct pattern of anomalies, including mental retardation, hearing impairment, unusual facial appearance, and skeletal defects. Both children have severe behavior disturbance and hyperactivity. The characteristic facial findings include a broad mouth, broad nasal bridge, mildly anteverted nares with a fleshy nasal tip, and deep nasolabial folds. Skeletal findings include mild to moderate short stature, dysharmonic maturation of epiphyseal ossification centers in the hands, and mild scoliosis.

Various theories have been postulated to account for the unusual inheritance pattern observed in the fragile X syndrome. The recent finding of a secondary amplification of the fragile X mutation in the offspring of carrier females [Oberle et al., 1991; Yu et al., 1991] is consistent with a maternal imprinting process. Laird [1987] has proposed that the fragile X mutation blocks complete reactivation of a previously inactivated fragile X chromosome. We have tested whether or not such a localized block extends as far distal as the red/green color-vision complex at Xq28. We found no evidence of color-vision defects among 25 male subjects with the fragile X syndrome. A fragile X positive woman also had normal color vision, despite being an obligate carrier of her father's gene for red/green color blindness. We conclude that the fragile X gene does not affect the function of neighboring color-vision genes, nor does it affect their ability to compensate adequately for inherited color deficiency on the homologous X chromosome in females.

We present two children--one, 47,XY, + mar, and the other, 47,XY, + 21. Both fathers were found to have a 47,XYY chromosome constitution. The initial assumption was that the fathers' aneuploid conditions contributed to those of the offspring. However, the derivation of the marker chromosome could be paternal, maternal, or postzygotic, and examination of polymorphic structures of the number 21 chromosomes of the child with Down syndrome and his parents suggested maternal derivation of the supernumerary 21. To explore further the reproductive risks of an individual with the XYY constitution, previous reports of reproductive performance and testicular histology are examined as are two theories which suggest XYY males may be at an increased risk of producing aneuploid progeny. Based on these reports, recommendations are made for testing XYY males prior to genetic counseling.

A 14-year-old white girl with mild dysostosis multiplex, odontoid hypoplasia, short stature, cloudy corneas, keratansulfaturia, but without detectable central nervous system abnormalities was referred with the diagnosis of Morquio syndrome. Clinical and roentgenographic findings were minimal compared to those of typical patients with the Morquio syndrome, MPS IV. Beta-Galactosidase activity in extracts of the patient's cultured fibroblasts was deficient, while that of galactosamine-6-sulfate sulfatase was normal. Conjunctival biopsy revealed intracytoplasmic vacuoles typical of lysosomal storage diseases. It is postulated that in this patient the deficiency of a beta-galactosidase is responsible for inadequate degradation of keratan sulfate and the appearance of a mild form of the Morquio syndrome (MPS IVB).

Computerized tomographic dimensions of the foramen magnum of 63 achondroplastic individuals were compared to standards established for nonachondroplastic individuals. The size of the foramen magnum in patients with achondroplasia was small at all ages, particularly in those with serious neurologic problems. The data suggest that measurement of the foramen magnum may identify achondroplastic individuals at high risk of developing neurologic complications.

The Nager syndrome was identified in a newborn infant and in a subsequent sib by prenatal ultrasonography. This report documents an autosomal recessive pattern of inheritance for this disorder.