Coffin‐Siris syndrome: Review and presentation of new cases from a questionnaire study

To clarify the phenotypic variability of Coffin‐Siris syndrome, we present a review of the literature and 18 new cases. We performed a questionnaire study of patients ascertained through an international support group. Information on their sibs was available for comparison. The most frequent findings include some degree of mental retardation or developmental delay, “coarse” facial appearance, feeding difficulties, frequent infections, and hypoplastic to absent fifth fingernails and fifth distal phalanges. We discuss the key manifestations for diagnosis, medical and developmental implications, and possible pathogenesis. © Wiley‐Liss. Inc.     

Patient with anomalous skin pigmentation expands the phenotype of ARID2 loss‐of‐function disorder,a SWI/SNF‐related intellectual disability

ARID2 loss‐of‐function is associated with a rare genetic disorder characterized in 14 reported patients to date. ARID2 encodes a member of the SWItch/sucrose non‐fermentable chromatin remodeling complex. Other genes encoding subunits of this complex, such as ARID1A, ARID1B, and SMARCA2, are mutated in association with Coffin‐Siris syndrome (CSS) and Nicolaides Baraitser syndrome (NCBRS) phenotypes. Previously reported ARID2 mutations manifested clinically with a CSS‐like phenotype including intellectual disability, coarsened facial features, fifth toenail hypoplasia, and other recognizable dysmorphisms. However, heterogeneity exists between previously reported patients with some patients showing more overlapping features with NCBRS. Herein, we present a patient with a novel disease‐causing ARID2 loss‐of‐function mutation. His clinical features included intellectual disability, coarse and dysmorphic facial features, toenail hypoplasia, ADHD, short stature, and delayed development consistent with prior reports. Our patient also presented with previously unreported clinical findings including ophthalmologic involvement, persistent fetal fingertip and toetip pads, and diffuse hyperpigmentary and hypopigmentary changes sparing his face, palms, and soles. The anomalous skin findings are particularly of interest given prior literature outlining the role of ARID2 in melanocyte homeostasis and melanoma. This clinical report and review of the literature is further affirming of the characteristic symptoms and expands the phenotype of this newly described and rare syndrome.     

CLOVES syndrome: review of a PIK3CA‐related overgrowth spectrum (PROS)

Overgrowth syndromes are characterized by global or localized disproportionate growth associated with other anomalies, including vascular malformations and neurological and/or visceral disorders. CLOVES (Congenital Lipomatous asymmetric Overgrowth of the trunk with lymphatic, capillary, venous, and combined‐type Vascular malformations, Epidermal naevi, Scoliosis/Skeletal and spinal anomalies) is an overgrowth syndrome caused by mosaic activating mutation in gene PIK3CA, which gives rise to abnormal PI3K‐AKT‐mTOR pathway activation. These mutations are responsible for the clinical manifestations of the syndrome, which include low‐ and high‐flow vascular malformations, thoracic lipomatous hyperplasia, asymmetric growth, and visceral and neurological disorders. These common anomalies are illustrated with figures from two personal cases. Identification of the clinical and genetic characteristics of CLOVES syndrome is crucial for the differential diagnosis with other overgrowth syndromes, such as Proteus or Klippel–Trenaunay (K–T) syndromes, and for the therapeutic management of the different anomalies. In this context, a new entity comprising different syndromes with phenotypic mutations in PIK3CA has been proposed, designated PIK3CA‐related overgrowth spectrum (PROS), with the aim of facilitating clinical management and establishing appropriate genetic study criteria.     

A 69‐year‐old woman with Coffin–Siris syndrome

Coffin–Siris syndrome (CSS) is a rare intellectual disability syndrome classically characterized by aplasia or hypoplasia of the distal phalanx or nail of the fifth and other digits, distinctive facial features, hirsutism/hypertrichosis, and sparce scalp hair. It is genetically heterogeneous but most often caused by a pathogenic variant in the ARID1B gene. Previous clinical reports of CSS patients are mainly based on young or middle‐aged individuals. Here, we report a 69‐year‐old woman with CSS phenotype and a pathogenic ARID1B loss‐of‐function variant c.5259_5260dup. She has severe intellectual disability but otherwise she is in relatively good health both physically and mentally. There is no evident history of chronic illness or progressive disability. CSS appears to be compatible with long survival and most likely it is underdiagnosed in geriatric patients with intellectual disability.     

Specific mosaic KRAS mutations affecting codon 146 cause oculoectodermal syndrome and encephalocraniocutaneous lipomatosis

Oculoectodermal syndrome (OES) and encephalocraniocutaneous lipomatosis (ECCL) are rare disorders that share many common features, such as epibulbar dermoids, aplasia cutis congenita, pigmentary changes following Blaschko lines, bony tumor‐like lesions, and others. About 20 cases with OES and more than 50 patients with ECCL have been reported. Both diseases were proposed to represent mosaic disorders, but only very recently whole‐genome sequencing has led to the identification of somatic KRAS mutations, p.Leu19Phe and p.Gly13Asp, in affected tissue from two individuals with OES. Here we report the results of molecular genetic studies in three patients with OES and one with ECCL. In all four cases, Sanger sequencing of the KRAS gene in DNA from lesional tissue detected mutations affecting codon 146 (p.Ala146Val, p.Ala146Thr) at variable levels of mosaicism. Our findings thus corroborate the evidence of OES being a mosaic RASopathy and confirm the common etiology of OES and ECCL. KRAS codon 146 mutations, as well as the previously reported OES‐associated alterations, are known oncogenic KRAS mutations with distinct functional consequences. Considering the phenotype and genotype spectrum of mosaic RASopathies, these findings suggest that the wide phenotypic variability does not only depend on the tissue distribution but also on the specific genotype.     

Extracutaneous manifestations in phacomatosis cesioflammea and cesiomarmorata: Case series and literature review

Phacomatosis pigmentovascularis (PPV) comprises a family of rare conditions that feature vascular abnormalities and melanocytic lesions that can be solely cutaneous or multisystem in nature. Recently published work has demonstrated that both vascular and melanocytic abnormalities in PPV of the cesioflammea and cesiomarmorata subtypes can result from identical somatic mosaic activating mutations in the genes GNAQ and GNA11. Here, we present three new cases of PPV with features of the cesioflammea and/or cesiomarmorata subtypes and mosaic mutations in GNAQ or GNA11. To better understand the risk of potentially occult complications faced by such patients we additionally reviewed 176 cases published in the literature. We report the frequency of clinical findings, their patterns of co‐occurrence as well as published recommendations for surveillance after diagnosis. Features assessed include: capillary malformation; dermal and ocular melanocytosis; glaucoma; limb asymmetry; venous malformations; and central nervous system (CNS) anomalies, such as ventriculomegaly and calcifications. We found that ocular findings are common in patients with phacomatosis cesioflammea and cesiomarmorata. Facial vascular involvement correlates with a higher risk of seizures (p = .0066). Our genetic results confirm the role of mosaic somatic mutations in GNAQ and GNA11 in phacomatosis cesioflammea and cesiomarmorata. Their clinical and molecular findings place these conditions on a clinical spectrum encompassing other GNAQ and GNA11 related disorders and inform recommendations for their management.     

Ophthalmic manifestations of lymphoma

BACKGROUND: Ophthalmic involvement in lymphoma is a relatively rare condition that can result from a primary intraocular lymphoma or an intraocular manifestation of systemic lymphoma. This report reviews the ophthalmic manifestations of lymphoma. METHODS: Review of relevant information from journal articles and Internet search. RESULTS: Almost all the structures in the orbit, adnexiae and eye can be involved in lymphoma. Lymphoma of the eye and adnexiae are most frequently of B lineage. Most of the ocular manifestations frequently masquerade as other more benign intraocular conditions including allergic or infectious conjunctivitis, uveitis, multiple evanescent white dot syndrome, acute retinal necrosis or herpetic retinitis. Correct diagnosis thus depends on a high index of suspicion and frequently requires radiologic imaging, histologic analysis, particularly vitreous biopsy or flow cytometry, subretinal aspiration and retinal biopsy. Diagnosis is often delayed and may lead to a fatal outcome. Recognition of its modes of presentation facilitates early diagnosis and treatment that may improve prognosis. CONCLUSIONS: It is important to review the ocular manifestations of lymphoma to assist the ophthalmologist to play a pivotal role in the prompt diagnosis and treatment of ocular lymphoma, and the haematologist/oncologist to recognize the need for a complete ophthalmic evaluation in the diagnosis, follow-up and management of lymphoma patients.     

A practical approach to ichthyoses with systemic manifestations

Inherited ichthyoses are rare disorders in terms of patient numbers, but abundant in terms of clinical‐genetic subtypes. These disorders are often associated with severe systemic manifestations, in addition to significant medical, cosmetic and social problems. There are 17 subtypes of syndromic ichthyosis identified so far and most patients with these syndromes are living in countries with high consanguinity rates. Frequently, clinicians cannot make a definitive diagnosis and patients are not managed properly owing to the rarity and complexity of these disorders. These difficulties make this group of ichthyosis and the patients living with them ‘orphan’. After skin and skin appendages, nervous system is the most frequently involved system in ichthyosis syndromes. Thus, association of ichthyosis with neurological symptoms provides an important clue for diagnosis. In this article, we aim to increase clinicians' comprehension of ichthyosis syndromes by providing a symptomatology‐based approach based on this observation. Additionally, we provide a review of ichthyosis syndromes, with special emphasis on neurological symptoms, hoping to attract interest to this complicated field.     

Epilepsy in Coffin–Siris syndrome: A report from the international CSS registry and review of the literature

Coffin–Siris syndrome (CSS, MIM135900) is a rare multiple congenital anomaly syndrome caused by pathogenic variants in the BAF complex; up to 28% of patients have previously been reported to have seizures, however, a comprehensive review of epilepsy has not been undertaken in this population. The International CSS Patient Report Database was queried for patients with self-reported seizures, epilepsy, and EEG results. Data gathered included demographic data, pathogenic gene variants, seizure characteristics and treatments, and EEG findings. In addition, a PubMed search was performed using keywords “Coffin–Siris syndrome” and “epilepsy,” “seizures,” or “EEG.” Results from relevant papers are reported. Twenty-four (7.2%) of 334 patients in the database reported having seizures, EEG abnormalities, and/or epilepsy. Median age of seizure onset was 2. 7 years. Fifteen of the 23 patients with seizures or epilepsy had an ARID1B causative variant. Seventeen patients (5.1%) reported EEG abnormalities, the majority of which were described as focal or multifocal (87.5%). In all but one patient, seizures were controlled on antiseizure medications (ASMs). The literature review yielded 311 unique CSS patients, 82 of which (26.4%) carried diagnoses of seizures or epilepsy. Details on seizure type(s), EEG findings, and response to treatment were limited.     

Ritscher‐Schinzel cranio‐cerebello‐cardiac (3C) syndrome: Report of four new cases and review

Ritscher‐Schinzel syndrome, also known as the 3C syndrome, is a rare, autosomal recessive syndrome characterized by craniofacial, cerebellar, and cardiac anomalies. Cardiac manifestations include ventricular septal defect, atrial septal defect, tetralogy of Fallot, double outlet right ventricle, hypoplastic left heart, aortic stenosis, pulmonic stenosis and other valvular anomalies. Central nervous system anomalies include Dandy‐Walker malformation, cerebellar vermis hypoplasia and enlargement of the cisterna magna. Craniofacial abnormalities seen are cleft palate, ocular coloboma, prominent occiput, low‐set ears, hypertelorism, down‐slanting palpebral fissures, depressed nasal bridge and micrognathia. Dandy‐Walker malformation, posterior fossa cyst, hydrocephalus and congenital heart defect are common malformations that may occur in isolation or as a part of many syndromes. Accurate genetic diagnosis and counseling require detailed analysis of the external as well as the internal anatomy and knowledge of the relative frequencies of various malformations in syndromes that may have overlapping clinical signs. We have had the opportunity recently to study four cases of the Ritscher‐Schinzel syndrome. A review of all reported cases is presented and an attempt made to define the minimum diagnostic criteria for the Ritscher‐Schinzel syndrome. Of the nine craniofacial anomalies commonly reported as a part of the Ritscher‐Schinzel syndrome, we consider two i.e., cleft palate and ocular coloboma, to be readily and objectively ascertainable. The other seven craniofacial traits, however, are somewhat subjective, require expert interpretation and are sometimes difficult to ascertain in a newborn or stillborn fetus. These are prominent forehead, prominent occiput, hypertelorism, down‐slanting palpebral fissures, low‐set ears, depressed nasal bridge and micrognathia. At least four of these were present in all cases that had a secure diagnosis of the Ritscher‐Schinzel syndrome. Thus, the criteria we propose to establish the diagnosis of the Ritscher‐Schinzel syndrome in a chromosomally normal sporadic case are the presence of cardiac malformation other than isolated patent ductus arteriosus, cerebellar malformation, and cleft palate or ocular coloboma or four of the following seven findings: prominent forehead, prominent occiput, hypertelorism, down‐slanting palpebral fissures, low‐set ears, depressed nasal bridge, and micrognathia. © 2001 Wiley‐Liss, Inc.     

Costello syndrome with severe cutis laxa and mosaic HRAS G12S mutation

Costello syndrome is a rare developmental disorder characterized by coarse face, postnatal growth retardation, skin and musculoskeletal anomalies, cardiovascular abnormalities, mental retardation, and tumor predisposition. Dermatological manifestations usually include redundant, soft and thickened skin. Loose skin is especially present over the neck, hands, and feet. Heterozygous missense mutations in HRAS are causative for Costello syndrome, with the c.34G?>?A (p.G12S) mutation as the most commonly found alteration. In the majority of affected individuals pathogenic sequence changes appeared de novo, however, two individuals with somatic mosaicism for the HRAS mutation have been reported. Here, we describe a boy with somatic mosaicism for the c.34G?>?A mutation in HRAS. Allelic quantitation revealed the mutation in approximately 58% of his lymphocytes; however, in DNA derived from buccal cells we could not detect the sequence change. The patient presented with the typical clinical findings of Costello syndrome such as increased birth weight, severe failure to thrive, characteristic facial appearance, and skin abnormalities. The dermatological anomalies were remarkable as he showed severe skin laxity with wrinkling of skin on all parts of the body due to loss of subcutaneous fat that decreased significantly by age 13 months. This case further adds to the phenotypic variability seen in patients with somatic mosaicism for an HRAS mutation and highlights the awareness of mosaic mutations in Costello syndrome when molecular testing is performed.     

Mosaicism for genome‐wide paternal uniparental disomy with features of multiple imprinting disorders: Diagnostic and management issues

Mosaicism for genome‐wide paternal uniparental disomy (UPD) has been reported in only seven live born individuals to date. Clinical presentation includes manifestations of multiple paternal UPD syndromes with high variability, likely due to the variable levels of mosaicism in different somatic tissues. We report an eighth case in a female patient with mosaicism for genome‐wide paternal UPD which highlights the complex clinical presentation. Our patient had features of Beckwith–Wiedemann syndrome (BWS), Angelman syndrome, and congenital hyperinsulinism. The clinical findings included prematurity, organomegaly, hemihyperplasia, developmental delay, benign tumors, and cystic lesions. The diagnosis in our patient was established utilizing microarray‐based genome‐wide DNA methylation analysis performed on leukocyte DNA. Targeted multiplex ligation‐dependent probe amplification (MLPA) analysis of chromosome regions 11p15 and 15q13 confirmed mosaicism for paternal UPD at these genomic regions. This case represents the first report of microarray‐based genome‐wide DNA methylation analysis in the diagnosis of genome‐wide paternal UPD. The application of microarray‐based genome‐wide DNA methylation analysis on selected individuals with complex clinical presentations could be a valuable diagnostic tool to improve the detection rate of mosaic genome‐wide paternal UPD. This approach, which screens many loci simultaneously, is more cost‐effective and less labor‐intensive than performing multiple targeted DNA methylation‐based assays. Identification of individuals with mosaicism for genome‐wide paternal UPD is an important goal as it confers a low recurrence risk for the family and identifies individuals who require surveillance due to increased tumor risk. © 2012 Wiley Periodicals, Inc.     

Mosaicism in von Hippel–Lindau disease with severe renal manifestations

von Hippel–Lindau (VHL) disease is an inheritable multisystem tumor syndrome characterized by multiple benign and malignant tumors affecting multiple organs. VHL is the result of a germline mutation in the VHL tumor suppressor gene. Molecular genomic analysis routinely confirms the clinical diagnosis. However, the use of molecular diagnostic methods can often be insufficient for the detection of mosaic germline VHL mutations, making the diagnosis of some cases of VHL difficult. Here, we report the case of a VHL mosaic patient with bilateral renal lesions in the absence of other VHL‐associated lesions. A VHL mutation was not originally detected by routine molecular testing. Nonetheless, the detection of a heterozygous c.194C>G (p.Ser65Trp) VHL mutation in the patient's daughter prompted further genetic assessment and eventually resulted in the finding of a mosaic c.194C>G (p.Ser65Trp) VHL mutation in the patient. The mutation rate was 18.8 ± 3.84% in peripheral leukocytes. As the frequency of VHL mosaicism remains underdetermined, the possibility of a diagnosis of mosaic VHL should be considered in patients with both typical and atypical VHL‐associated manifestations.     

Novel FREM1 mutations expand the phenotypic spectrum associated with manitoba‐oculo‐tricho‐anal (MOTA) syndrome and bifid nose renal agenesis anorectal malformations (BNAR) syndrome

Loss of function mutations in FREM1 have been demonstrated in Manitoba‐oculo‐tricho‐anal (MOTA) syndrome and Bifid Nose Renal Agenesis and Anorectal malformations (BNAR) syndrome, but the wider phenotypic spectrum that is associated with FREM1 mutations remains to be defined. We screened three probands with phenotypic features of MOTA syndrome. In one severely affected infant who was diagnosed with MOTA syndrome because of bilateral eyelid colobomas, a bifid nasal tip, hydrometrocolpos and vaginal atresia, we found two nonsense mutations that likely result in complete loss of FREM1 function. This infant also had renal dysplasia, a finding more consistent with BNAR syndrome. Another male who was homozygous for a novel stop mutation had an extensive eyelid colobomas, corneopalpebral synechiae, and unilateral renal agenesis. A third male child diagnosed with MOTA syndrome because of corneopalpebral synechiae and eyelid colobomas had a homozygous splice site mutation in FREM1. These cases illustrate that disruption of the FREM1 gene can produce a spectrum of clinical manifestations encompassing the previously described MOTA and BNAR syndromes, and that features of both syndromes may be seen in the same individual. The phenotype of FREM1‐related disorders is thus more pleiotropic than for MOTA and BNAR syndrome alone and more closely resembles the widespread clinical involvement seen with Fraser syndrome. Moreover, our first case demonstrates that vaginal atresia may be a feature of FREM1‐related disorders. © 2013 Wiley Periodicals, Inc.     

Clinical,cytogenetic, and molecular evidence for an infant with Smith–Magenis syndrome born from a mother having a mosaic 17p11.2p12 deletion

We describe an infant with del(17) (p11.2p12) whose deleted chromosome was inherited from a mosaic mother. The child had manifestations consistent with Smith–Magenis syndrome. The mother appeared to be of normal intelligence and she had minimal findings of Smith–Magenis syndrome. Separation of chromosome 17 homologues in somatic cell hybrids and molecular studies confirmed the cytogenetic diagnoses and the fact that the mother was mosaic. Furthermore, molecular analysis demonstrated novel breakpoints in this family, with the deletion extending into and completely encompassing the markers duplicated in Charcot-Marie-Tooth (CMT) disease. Although this Smith–Magenis syndrome patient is completely deleted for the CMT region, her electrophysiological findings are different from those found in CMT. This is the only reported case of Smith–Magenis syndrome with transmission from a partially affected mosaic mother. Transmission of interstitial deletions from mosaic parents may be more common than thought; therefore, parental chromosomes should be examined when interstitial deletions are identified. © 1993 Wiley-Liss, Inc.     

Distinct phenotype of PHF6 deletions in females

We report on two female patients carrying small overlapping Xq26.2 deletions of 100 kb and 270 kb involving the PHF6 gene. Mutations in PHF6 have been reported in individuals with Borjeson–Forssman–Lehmann syndrome, a condition present almost exclusively in males. Two very recent papers revealed de novo PHF6 defects in seven female patients with intellectual disability and a phenotype resembling Coffin–Siris syndrome (sparse hair, bitemporal narrowing, arched eyebrows, synophrys, high nasal root, bulbous nasal tip, marked clinodactyly with the hypoplastic terminal phalanges of the fifth fingers and cutaneous syndactyly of the toes, Blaschkoid linear skin hyperpigmentation, dental anomalies and occasional major malformations). The clinical presentation of these patients overlaps completely with our first patient, who carries a germline deletion involving PHF6. The second patient has a mosaic deletion and presented with a very mild phenotype of PHF6 loss in females. Our report confirms that PHF6 loss in females results in a recognizable phenotype overlapping with Coffin–Siris syndrome and distinct from Borjeson–Forssman–Lehmann syndrome. We expand the clinical spectrum and provide the first summary of the recommended medical evaluation.     

Growth charts for individuals with Coffin‐Siris syndrome

Coffin‐Siris syndrome (CSS; OMIM #135900) is a rare, multisystem syndrome caused by pathogenic variants in genes encoding the BRG‐1 associated factors complex (BAF). Individuals with CSS often present with feeding difficulties and failure to thrive during infancy, in addition to a number of variable congenital anomalies. Nutritional interventions are used to support growth in this population, and growth hormone therapy has been reported in a limited number of cases. The purpose of this study was to construct CSS‐specific growth charts to better characterize the growth in this population. Anthropometric data were collected from 99 individuals enrolled in the CSS/BAF pathway international registry via a retrospective chart review. All measurements obtained after the first exposure to growth hormone therapy were excluded from this analysis. Sex‐specific centiles (5th, 50th, and 95th) were estimated for height, weight, and head circumference from birth to age 10. Cubic smoothing splines were then fit to the centile estimates and superimposed on normative male and female growth curves for comparison. The CSS patients in this cohort exhibited normal growth parameters at birth. By age 10, the weight and head circumference of the CSS cohort began to approach normal parameters. Stature, however, remained shortened at 10 years of age.