A pigmentary skin defect is a new finding in Marshall-Smith syndrome

Marshall–Smith Syndrome (OMIM 602535) was described initially by Marshall in two infants with a syndrome characterized by accelerated skeletal maturation, failure to thrive, and dysmorphic facial features. We report a new patient with clinical features of Marshall–Smith syndrome with additional findings such as hyperpigmented lines on trunk and the four extremities. © 2011 Wiley‐Liss, Inc.     

A girl with the Weaver syndrome.

A female with the Weaver syndrome is reported. In addition to the characteristic manifestations of overgrowth and advanced bone age, the facies were typical, with a broad forehead, hypertelorism, a long philtrum, micrognathia, and large ears. Like most other patients with Weaver syndrome, she was developmentally delayed, hypertonic, and had a hoarse voice. Other clinical features included prominent finger pads, narrow hyperconvex nails, small and narrow chest, unilateral dislocated distal ulna, and abnormal thoracic vertebrae.     

Costello syndrome.

Costello syndrome is characterised by postnatal growth deficiency, coarse facies, redundant skin on the neck, palms, soles, and fingers, dark skin, acanthosis nigricans, and papillomata. The natural history evolves in two phases, a severe failure to thrive during the first months contrasting with a normal weight gain in later life. Cardiomyopathy is frequent but other visceral involvement is rare. Mild to moderate mental retardation is usual and most patients exhibit a characteristic sociable and friendly personality. The pathogenesis and molecular basis of the syndrome are unknown and the diagnosis is reliant on clinical expertise. Papillomata represent the most characteristic manifestation but may arise late in life. The peculiar course of the disease, the typical facies, and the ectodermal involvement with loose and hyperpigmented skin are characteristic enough to allow an early diagnosis. Most cases have been sporadic, suggesting de novo dominant mutations.     

Further delineation of Malan syndrome

Malan syndrome is an overgrowth disorder described in a limited number of individuals. We aim to delineate the entity by studying a large group of affected individuals. We gathered data on 45 affected individuals with a molecularly confirmed diagnosis through an international collaboration and compared data to the 35 previously reported individuals. Results indicate that height is > 2 SDS in infancy and childhood but in only half of affected adults. Cardinal facial characteristics include long, triangular face, macrocephaly, prominent forehead, everted lower lip, and prominent chin. Intellectual disability is universally present, behaviorally anxiety is characteristic. Malan syndrome is caused by deletions or point mutations of NFIX clustered mostly in exon 2. There is no genotype‐phenotype correlation except for an increased risk for epilepsy with 19p13.2 microdeletions. Variants arose de novo, except in one family in which mother was mosaic. Variants causing Malan and Marshall‐Smith syndrome can be discerned by differences in the site of stop codon formation. We conclude that Malan syndrome has a well recognizable phenotype that usually can be discerned easily from Marshall–Smith syndrome but rarely there is some overlap. Differentiation from Sotos and Weaver syndrome can be made by clinical evaluation only.     

Marshall-Smith syndrome: natural history and evidence of an osteochondrodysplasia with connective tissue abnormalities

The Marshall-Smith syndrome (MSS) is a distinct malformation syndrome characterized by accelerated skeletal maturation, relative failure to thrive, respiratory difficulties, mental retardation, and unusual facies, including prominent forehead, shallow orbits, blue sclerae, depressed nasal bridge, and micrognathia. At least 33 cases have been reported in the literature, mostly as single case reports or small series. The purpose of the present study is to report on the clinical findings and natural history of MSS in five children and to review the features of three others previously reported, with particular attention to the skeletal and connective tissue findings. Our study demonstrates an increased rate of nontraumatic fractures and other bony and connective tissue abnormalities that support the hypothesis that MSS should be considered an osteochondrodysplasia. In addition, long-term survival beyond infancy is possible if respiratory problems are expectantly and aggressively managed.     

Familial neurofibromatosis type 1 associated with an overgrowth syndrome resembling Weaver syndrome.

The simultaneous occurrence of familial neurofibromatosis type 1 (NF1) and an overgrowth syndrome resembling Weaver syndrome was observed in two related cases (a mother and her son). NF1 was confirmed by molecular genetic analysis showing a large deletion at 17q11.2, encompassing the entire NF1 gene. The other symptoms in the two cases were similar to the features reported in Weaver syndrome. Although the combination of NF1 and an overgrowth syndrome resembling Weaver syndrome in this family may be fortuitous, we favour the hypothesis that the deletion of the entire gene has caused this combined phenotype. Possible pathogenetic mechanisms are discussed. The observation suggests a relation between NF1 with an extraordinarily large gene deletion and a Weaver(-like) syndrome. This warrants investigation for deletions in the 17q11.2 region in Weaver(-like) syndrome patients.     

Unbalanced 13;18 translocation and Williams syndrome.

A 2 1/2 year old girl is reported with a de novo 13;18 unbalanced translocation and the facial features of Williams syndrome, subaortic stenosis, failure to thrive, and developmental delay. This case provides two candidate locations for the underlying molecular pathology of this sporadic syndrome. Williams syndrome is associated with intellectual and growth retardation, infantile feeding problems which may be associated with hypercalcaemia, cardiovascular abnormalities, a friendly, loquacious personality, and a typical facies. The cause is not known and only a few chromosome abnormalities have been reported in patients with the Williams syndrome phenotype. Many papers fail to mention chromosome studies. We report a girl with an unbalanced 13;18 translocation and the Williams syndrome phenotype.     

Cervical spine anomalies and tumors in Weaver syndrome

Weaver syndrome is an autosomal dominant disorder comprising accelerated growth rate and rapidly advancing skeletal maturation. Previous reports suggest that the phenotype in adults may be sufficiently subtle to make diagnosis difficult. Half brothers with classical childhood findings of Weaver syndrome and their father with minimal clinical findings showed cervical spine anomalies that likely represent a consistent radiographic finding in this disorder. One of the children represents the third occurrence of neoplasia in Weaver syndrome.     

A Japanese male infant with the Weaver syndrome

A 15-month-old male infant who had pre- and postnatal overgrowth, accelerated bone maturation and characteristic facial appearance was described. Although a Japanese female with Weaver syndrome previously reported had slightly different clinical manifestations from others, our patient had typical clinical features of Weaver syndrome. We suggest that a genetic mutation of the syndrome may be the same in Japanese as other ethnic groups and that Weaver syndrome may be an autosomal dominant disorder with variable expressions.     

A new autosomal recessive disorder resembling Weaver syndrome

Most reported cases of Weaver syndrome are sporadic, and the mode of inheritance is still unclear. We describe two (male and female) sibs born to consanguineous Bedouin parents with manifestations resembling Weaver syndrome. Both sibs had accelerated growth of prenatal onset, hypotonia, psychomotor retardation, excess loose skin, peculiar craniofacial and acral anomalies, dental dysplasia and/or serrated gums, joint laxity, and hoarse low-pitched cry. One of them had an accelerated harmonic skeletal maturation. Differentiating features from Weaver syndrome are discussed, and autosomal recessive inheritance is suggested.     

Twins and their mildly affected mother with Weaver syndrome

Dumić M, Vuković J, Cvitković M, Medica I. Twins and their mildly affected mother with Weaver syndrome. Clin Genet 1993: 44: 338–340. © Munksgaard, 1993
A pair of twins, a brother and sister, with the complete form of Weaver syndrome (overgrowth, macrocephaly, facial, skeletal, nail and feet anomalies) and their mildly affected mother are reported, suggesting autosomal dominant inheritance. They all have plantar and palmar hyper-hydrosis and twins also have nail dysplasia, symptoms which have not yet been described in this syndrome.     

Weaver syndrome with neuroblastoma and cardiovascular anomalies

We report on an infant with Weaver syndrome, neoplasia and cardiovascular anomalies. Stage 4S neuroblastoma underwent spontaneous resolution. Three neoplasms have been reported in Weaver syndrome: another stage 4S neuroblastoma [Muhonen and Menezes, 1990: J Pediatr 116:596-599], an ovarian endodermal sinus tumor [Derry et al., 1999: J Med Genet 36:725-728], and a sacrococcygeal teratoma [Kelly et al., 2000: Am J Med Genet 95:492-495]. No case was associated with cardiovascular anomalies. Our patient had VSD and PDA, and although several other patients with Weaver syndrome have had cardiovascular anomalies, they were shown not to have neoplasia.     

Congenital hypoparathyroidism, seizure, extreme growth failure with developmental delay and dysmorphic features—another case of this new syndrome

A 4-year-old Saudi female child with extreme failure to thrive, striking dysmorphic features, developmental delay, congenital hypoparathyroidism, UTI, seizures, chronic otitis media, chronic non-specific gastroenteritis and repeated life-threatening infections was followed from birth. She was the product of first-cousin consanguineous marriage. She had striking facies with frontal prominence, deep-set eyes, depressed nasal bridge, beaked nose, long philtrum with thin upper lip, micrognathia, large floppy ears, bifid uvula, and growth retardation with SD score less than -2 for height, weight and head circumference. We believe these features which include congenital hypoparathyroidism, severe growth failure and developmental delay in the absence of chromosomal abnormality represent a newly described genetically determined syndrome.     

Neurologic and gastrointestinal dysfunction in cardio‐facio‐cutaneous syndrome: Identification of a severe phenotype

Controversy exists over the distinction between cardio‐facio‐cutaneous (CFC) syndrome and Noonan syndrome (NS). Several authors have suggested that they are different phenotypes of the same condition. We present the cases of two patients with CFC syndrome to show that it is a distinct condition with a unique combination of findings and a more complex natural history. These patients, both girls, were born with signs of fetal edema following pregnancies complicated by polyhydramnios. Each has short stature with relative macrocephaly; fuzzy, sparse hair; and the typical craniofacial features, including a square forehead. Both have heart abnormalities, failure to thrive, and severe feeding problems requiring gastrostomy. They are markedly hypotonic and developmentally delayed. They show signs of frequent eyelid fluttering and have oral aversion, tactile hypersensitivity, and sensory integration abnormalities. Keratosis pilaris, the characteristic skin symptom, is also present in both patients. In a review we identified 56 cases of CFC syndrome. We scored these cases by 10 clinical criteria and identified a subset with a specific, severe phenotype distinct from that of NS. The serious neurologic and gastrointestinal complications, in addition to the skin abnormalities and characteristic facies in this group, clearly separate these patients from the mildly affected ones, most of whom appear to have NS or another syndrome. We discuss the differences between the severe CFC phenotype and those of overlapping conditions. We set forth stringent diagnostic criteria for CFC syndrome, the initial step toward identifying a molecular basis for this condition. Am. J. Med. Genet. 95:135–143, 2000. © 2000 Wiley‐Liss, Inc.     

Neurologic and gastrointestinal dysfunction in cardio-facio-cutaneous syndrome: identification of a severe phenotype

Controversy exists over the distinction between cardio-facio-cutaneous (CFC) syndrome and Noonan syndrome (NS). Several authors have suggested that they are different phenotypes of the same condition. We present the cases of two patients with CFC syndrome to show that it is a distinct condition with a unique combination of findings and a more complex natural history. These patients, both girls, were born with signs of fetal edema following pregnancies complicated by polyhydramnios. Each has short stature with relative macrocephaly; fuzzy, sparse hair; and the typical craniofacial features, including a square forehead. Both have heart abnormalities, failure to thrive, and severe feeding problems requiring gastrostomy. They are markedly hypotonic and developmentally delayed. They show signs of frequent eyelid fluttering and have oral aversion, tactile hypersensitivity, and sensory integration abnormalities. Keratosis pilaris, the characteristic skin symptom, is also present in both patients. In a review we identified 56 cases of CFC syndrome. We scored these cases by 10 clinical criteria and identified a subset with a specific, severe phenotype distinct from that of NS. The serious neurologic and gastrointestinal complications, in addition to the skin abnormalities and characteristic facies in this group, clearly separate these patients from the mildly affected ones, most of whom appear to have NS or another syndrome. We discuss the differences between the severe CFC phenotype and those of overlapping conditions. We set forth stringent diagnostic criteria for CFC syndrome, the initial step toward identifying a molecular basis for this condition.     

EED and EZH2 constitutive variants: A study to expand the Cohen‐Gibson syndrome phenotype and contrast it with Weaver syndrome

Overgrowth‐intellectual disability (OGID) syndromes are characterized by increased growth (height and/or head circumference ≥+2 SD) in association with an intellectual disability. Constitutive EED variants have previously been reported in five individuals with an OGID syndrome, eponymously designated Cohen‐Gibson syndrome and resembling Weaver syndrome. Here, we report three additional individuals with constitutive EED variants, identified through exome sequencing of an OGID patient series. We compare the EED phenotype with that of Weaver syndrome (56 individuals), caused by constitutive EZH2 variants. We conclude that while there is considerable overlap between the EED and EZH2 phenotypes with both characteristically associated with increased growth and an intellectual disability, individuals with EED variants more frequently have cardiac problems and cervical spine abnormalities, boys have cryptorchidism and the facial gestalts can usually be distinguished.     

Autosomal dominant inheritance of Weaver syndrome.

Most report of Weaver syndrome have been sporadic cases and the genetic basis of the syndrome is uncertain. This report of an affected father and daughter provides evidence for autosomal dominant inheritance.     

Asymmetric crying facies with microcephaly and mental retardation. An autosomal dominant syndrome with variable expressivity

An infant boy with asymmetric crying facies, microcephaly, developmental retardation and failure to thrive is reported. His two siblings died in the newborn period because of complex congenital heart defects. The mother and the maternal grandmother have asymmetric crying facies, microcephaly and normal intelligence. A maternal aunt has severe physical and mental retardation, facial asymmetry, microcephaly, and cleft palate. This family allows an expansion of the spectrum of malformations associated with asymmetric crying facies and suggests autosomal dominant inheritance with variable expressivity.     

Deletions in the 3′ Part of the NFIX Gene Including a Recurrent Alu‐Mediated Deletion of Exon 6 and 7 Account for Previously Unexplained Cases of Marshall–Smith Syndrome

Marshall–Smith syndrome (MSS) is a very rare malformation syndrome characterized by typical craniofacial anomalies, abnormal osseous maturation, developmental delay, failure to thrive, and respiratory difficulties. Mutations in the nuclear factor 1/X gene (NFIX) were recently identified as the cause of MSS. In our study cohort of 17 patients with a clinical diagnosis of MSS, conventional sequencing of NFIX revealed frameshift and splice‐site mutations in 10 individuals. Using multiplex ligation‐dependent probe amplification analysis, we identified a recurrent deletion of NFIX exon 6 and 7 in five individuals. We demonstrate this recurrent deletion is the product of a recombination between AluY elements located in intron 5 and 7. Two other patients had smaller deletions affecting exon 6. These findings show that MSS is a genetically homogeneous Mendelian disorder. RT‐PCR experiments with newly identified NFIX mutations including the recurrent exon 6 and 7 deletion confirmed previous findings indicating that MSS‐associated mutant mRNAs are not cleared by nonsense‐mediated mRNA decay. Predicted MSS‐associated mutant NFIX proteins consistently have a preserved DNA binding and dimerization domain, whereas they grossly vary in their C‐terminal portion. This is in line with the hypothesis that MSS‐associated mutations encode dysfunctional proteins that act in a dominant negative manner.     

Mutations in NSD1 are responsible for Sotos syndrome, but are not a frequent finding in other overgrowth phenotypes

Recently, deletions encompassing the nuclear receptor binding SET-Domain 1 (NSD1) gene have been described as the major cause of Japanese patients with the Sotos syndrome, whereas point mutations have been identified in the majority of European Sotos syndrome patients. In order to investigate a possible phenotype-genotype correlation and to further define the predictive value of NSD1 mutations, we performed mutational analysis of the NSD1 gene in 20 patients and one familial case with Sotos syndrome, five patients with Weaver syndrome, six patients with unclassified overgrowth/mental retardation, and six patients with macrocephaly/mental retardation. We were able to identify mutations within the NSD1 gene in 18 patients and the familial case with Sotos syndrome (90%). The mutations (six nonsense, eight frame shifts, three splice site, one missense, one in-frame deletion) are expected to result in an impairment of NSD1 function. The best correlation between clinical assessment and molecular results was obtained for the Sotos facial gestalt in conjunction with overgrowth, macrocephaly, and developmental delay. In contrast to the high mutation detection rate in Sotos syndrome, none of the patients with Weaver syndrome, unclassified overgrowth/mental retardation and macrocephaly/mental retardation, harbored NSD1 mutations. We tested for large deletions by FISH analysis but were not able to identify any deletion cases. The results indicate that the great majority of patients with Sotos syndrome are caused by mutations in NSD1. Deletions covering the NSD1 locus were not found in the patients analyzed here.