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Cornelia de Lange syndrome is a rare developmental malformation syndrome characterized by small stature, limb anomalies, distinctive facial features, developmental delays, and behavioral issues. The diagnosis of Cornelia de Lange syndrome is made clinically or on the basis of an identified variant in one of the genes associated with Cornelia de Lange syndrome. SMC1A variants are the cause of 5% of the cases of Cornelia de Lange syndrome. SMC1A is located on the X-chromosome and is thought to escape X-inactivation in some females. Patients with SMC1A variants are being increasingly identified through panel testing or exome sequencing without prior clinical suspicion of Cornelia de Lange syndrome. In general, intractable epilepsy is not considered a prominent feature of Cornelia de Lange syndrome, yet this is found in these patients with SMC1A variants. Here we report on a series of patients with SMC1A variants and intractable epilepsy. In contrast to patients with typical SMC1A-associated Cornelia de Lange syndrome, all of the identified patients were female, and when available, X-inactivation studies were highly skewed with truncating variants. We describe the medical involvement and physical appearance of the participants, compared to the diagnostic criteria used for classical Cornelia de Lange syndrome. We also report on the clinical characteristics of the epilepsy, including age of onset, types of seizures, electroencephalographic (EEG) findings, and response to various antiepileptic medications. These findings allow us to draw conclusions about how this population of patients with SMC1A variants fit into the spectrum of Cornelia de Lange syndrome and the broader spectrum of cohesinopathies and allow generalizations that may impact clinical care and, in particular, epilepsy management.

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Cornelia de Lange syndrome (CdLS) is a spectrum disorder due to variants in genes of the cohesin protein complex. The following abstracts are from the Cornelia de Lange Syndrome Scientific and Educational Symposium held virtually in October 2020. Aspects of behavior, including autistic features, impulsivity, adaptive skills, executive function, and anxiety are described. Applied behavioral analysis is a promising approach for autism, and an N-acetylcysteine trial is proposed. Children below 6 years with CdLS have an increased number of and further travel to medical providers, with insurance type comprising a significant barrier. Speech, language, and feeding abilities fall significantly below expectations for age in CdLS. Augmentative alternative communication can yield potential barriers as well as interesting benefits. Developmentally, studies in animal models further elucidate the mechanisms and roles of cohesin: link with mediator transcriptional complex; facilitation of enhancer-promoter communication; regulation of gene expression; allocation of cells to germ layers; and repair of spontaneous DNA damage in placental cells. Genome and RNA sequencing can help identify the molecular cause in the 20% of individuals with suspected CdLS and negative testing. The phenotypes in individuals with variants in the SMC1A gene are distinct, and that with intractable seizures has been further evaluated. AMA CME credits provided by GBMC, Baltimore, MD. All studies approved by an ethics committee.

Au-Kline syndrome (AKS) is a neurodevelopmental disorder associated with multiple malformations and a characteristic facial gestalt. The first individuals ascertained carried de novo loss-of-function (LoF) variants in HNRNPK. Here, we report 32 individuals with AKS (26 previously unpublished), including 13 with de novo missense variants. We propose new clinical diagnostic criteria for AKS that differentiate it from the clinically overlapping Kabuki syndrome and describe a significant phenotypic expansion to include individuals with missense variants who present with subtle facial features and few or no malformations. Many gene-specific DNA methylation (DNAm) signatures have been identified for neurodevelopmental syndromes. Because HNRNPK has roles in chromatin and epigenetic regulation, we hypothesized that pathogenic variants in HNRNPK may be associated with a specific DNAm signature. Here, we report a unique DNAm signature for AKS due to LoF HNRNPK variants, distinct from controls and Kabuki syndrome. This DNAm signature is also identified in some individuals with de novo HNRNPK missense variants, confirming their pathogenicity and the phenotypic expansion of AKS to include more subtle phenotypes. Furthermore, we report that some individuals with missense variants have an "intermediate" DNAm signature that parallels their milder clinical presentation, suggesting the presence of an epi-genotype phenotype correlation. In summary, the AKS DNAm signature may help elucidate the underlying pathophysiology of AKS. This DNAm signature also effectively supported clinical syndrome delineation and is a valuable aid for variant interpretation in individuals where a clinical diagnosis of AKS is unclear, particularly for mild presentations. ispartof: AMERICAN JOURNAL OF HUMAN GENETICS vol:109 issue:10 pages:1867-1884 ispartof: location:United States status: published

International audience; Congenital anomalies of the kidney and urinary tract (CAKUT) constitute one of the most frequent birth defects and represent the most common cause of chronic kidney disease in the first three decades of life. Despite the discovery of dozens of monogenic causes of CA-KUT, most pathogenic pathways remain elusive. We performed whole-exome sequencing (WES) in 551 individuals with CAKUT and identified a heterozygous de novo stop-gain variant in ZMYM2 in two different families with CAKUT. Through collaboration, we identified in total 14 different heterozygous loss-of-function mutations in ZMYM2 in 15 unrelated families. Most mutations occurred de novo, indicating possible interference with reproductive function. Human disease features are replicated in X. tropicalis larvae with morpho-lino knockdowns, in which expression of truncated ZMYM2 proteins, based on individual mutations, failed to rescue renal and cranio-facial defects. Moreover, heterozygous Zmym2-deficient mice recapitulated features of CAKUT with high penetrance. The ZMYM2 protein is a component of a transcriptional corepressor complex recently linked to the silencing of developmentally regulated endoge-nous retrovirus elements. Using protein-protein interaction assays, we show that ZMYM2 interacts with additional epigenetic silencing complexes, as well as confirming that it binds to FOXP1, a transcription factor that has also been linked to CAKUT. In summary, our findings establish that loss-of-function mutations of ZMYM2, and potentially that of other proteins in its interactome, as causes of human CAKUT, offering new routes for studying the pathogenesis of the disorder.

Cornelia de Lange syndrome is a rare developmental malformation syndrome characterized by small stature, limb anomalies, distinctive facial features, developmental delays, and behavioral issues. The diagnosis of Cornelia de Lange syndrome is made clinically or on the basis of an identified variant in one of the genes associated with Cornelia de Lange syndrome.

We recently described a new neurodevelopmental syndrome (TAF1/MRXS33 intellectual disability syndrome) (MIM# 300966) caused by pathogenic variants involving the X-linked gene TAF1, which participates in RNA polymerase II transcription. The initial study reported eleven families, and the syndrome was defined as presenting early in life with hypotonia, facial dysmorphia, and developmental delay that evolved into intellectual disability (ID) and/or autism spectrum disorder (ASD). We have now identified an additional 27 families through a genotype-first approach. Familial segregation analysis, clinical phenotyping, and bioinformatics were capitalized on to assess potential variant pathogenicity, and molecular modelling was performed for those variants falling within structurally characterized domains of TAF1. A novel phenotypic clustering approach was also applied, in which the phenotypes of affected individuals were classified using 51 standardized Human Phenotype Ontology (HPO) terms. Phenotypes associated with TAF1 variants show considerable pleiotropy and clinical variability, but prominent among previously unreported effects were brain morphological abnormalities, seizures, hearing loss, and heart malformations. Our allelic series broadens the phenotypic spectrum of TAF1/MRXS33 intellectual disability syndrome and the range of TAF1 molecular defects in humans. It also illustrates the challenges for determining the pathogenicity of inherited missense variants, particularly for genes mapping to chromosome X. This article is protected by copyright. All rights reserved.

Cornelia de Lange syndrome (CdLS) is a dominant multisystemic malformation syndrome due to mutations in five genes-NIPBL, SMC1A, HDAC8, SMC3, and RAD21. The characteristic facial dysmorphisms include microcephaly, arched eyebrows, synophrys, short nose with depressed bridge and anteverted nares, long philtrum, thin lips, micrognathia, and hypertrichosis. Most affected individuals have intellectual disability, growth deficiency, and upper limb anomalies. This study looked at individuals from diverse populations with both clinical and molecularly confirmed diagnoses of CdLS by facial analysis technology. Clinical data and images from 246 individuals with CdLS were obtained from 15 countries. This cohort included 49% female patients and ages ranged from infancy to 37 years. Individuals were grouped into ancestry categories of African descent, Asian, Latin American, Middle Eastern, and Caucasian. Across these populations, 14 features showed a statistically significant difference. The most common facial features found in all ancestry groups included synophrys, short nose with anteverted nares, and a long philtrum with thin vermillion of the upper lip. Using facial analysis technology we compared 246 individuals with CdLS to 246 gender/age matched controls and found that sensitivity was equal or greater than 95% for all groups. Specificity was equal or greater than 91%. In conclusion, we present consistent clinical findings from global populations with CdLS while demonstrating how facial analysis technology can be a tool to support accurate diagnoses in the clinical setting. This work, along with prior studies in this arena, will assist in earlier detection, recognition, and treatment of CdLS worldwide.

Hypermobile Ehlers-Danlos syndrome (hEDS) is a common disorder in children and adolescents that negatively impacts health-related quality of life (HRQOL). It can include chronic pain, fatigue, autonomic dysfunction, and mood problems. The objective of this study was to examine levels of agreement between children and parents in the setting of hEDS and HRQOL. Individuals with hEDS, ages 10-20 years, and their parents were recruited to complete a series of surveys. Instruments included pediatric quality of life generic and multidimensional fatigue scales, Functional Disability Index, Pain-Frequency-Severity-Duration scale, Brief Illness Perception Questionnaire, and Herth Hope Index. Agreement on each measure was evaluated using statistical calculations. Thirty-six parent-child dyads completed the surveys. There were no significant differences between the means of parent and child scores. There was moderate to strong agreement on all survey scores. However, the proportion of dyads with disagreement was relatively high for each individual score. Eighteen dyads disagreed on at least half of the surveys. Body mass index centile and child perception of cognitive fatigue most strongly predicted disagreement in total HRQOL score. Proxy-reporters for children and adolescents with hEDS may agree with their child on average. However, due to significant frequency of clinically important disagreement, information from both children and their parents should be sought whenever possible.

Background Cornelia de Lange Syndrome (CdLS) is a rare congenital disorder characterized by typical facial features, growth failure, limb abnormalities, and gastroesophageal dysfunction that may be caused by mutations in several genes that disrupt gene regulation early in development. Symptoms in individuals with CdLS suggest that the peripheral nervous system (PNS) is involved, yet there is little direct evidence. Method Somatic nervous system was evaluated by conventional motor and sensory nerve conduction studies and autonomic nervous system by heart rate variability, sympathetic skin response and sudomotor testing. CdLS Clinical Score and genetic studies were also obtained. Results Sympathetic skin response and sudomotor test were pathological in 35% and 34% of the individuals with CdLS, respectively. Nevertheless, normal values in large fiber nerve function studies. Conclusions Autonomic nervous system (ANS) dysfunction is found in many individuals with Cornelia de Lange Syndrome, and could be related to premature aging.

Cornelia de Lange syndrome (CdLS) is associated with repetitive and self-injurious behaviors (RBs, SIB). Evaluating children with CdLS, this study: (1) characterizes the spectrum of RBs; (2) characterizes the impact and severity of RBs including SIB; (3) describes how age and adaptive functioning relate to RBs including SIB. Fifty children (5–17 years) with CdLS were assessed with Children’s Yale-Brown Obsessive Compulsive Scale Modified for PDD; Aberrant Behavior Checklist (ABC); Vineland Adaptive Behaviors Scales (VABS). All children had ≥ 1 type of RB; 44% had some form of SIB. 64% spent > 1 h/day displaying RBs. Lower VABS adaptive functioning was associated with higher stereotypy and SIB scores (ABC). In children with CdLS, RBs including SIB are common, impactful, and associated with lower adaptive functioning.

Cornelia de Lange syndrome (CdLS) is an archetypical genetic syndrome that is characterized by intellectual disability, well-defined facial features, upper limb anomalies and atypical growth, among numerous other signs and symptoms. It is caused by variants in any one of seven genes, all of which have a structural or regulatory function in the cohesin complex. Although recent advances in next-generation sequencing have improved molecular diagnostics, marked heterogeneity exists in clinical and molecular diagnostic approaches and care practices worldwide. Here, we outline a series of recommendations that document the consensus of a group of international experts on clinical diagnostic criteria, both for classic CdLS and non-classic CdLS phenotypes, molecular investigations, long-term management and care planning., Cornelia de Lange syndrome is a genetic disorder affecting multiple organ systems that exhibits great phenotypic heterogeneity. This Consensus Statement summarizes recommendations for the diagnosis and management of patients with Cornelia de Lange syndrome.

Neurodevelopment is a transcriptionally orchestrated process. Cyclin K, a regulator of transcription encoded by CCNK, is thought to play a critical role in the RNA polymerase II-mediated activities. However, dysfunction of CCNK has not been linked to genetic disorders. In this study, we identified three unrelated individuals harboring de novo heterozygous copy number loss of CCNK in an overlapping 14q32.3 region and one individual harboring a de novo nonsynonymous variant c.331A>G (p.Lys111Glu) in CCNK. These four individuals, though from different ethnic backgrounds, shared a common phenotype of developmental delay and intellectual disability (DD/ID), language defects, and distinctive facial dysmorphism including high hairline, hypertelorism, thin eyebrows, dysmorphic ears, broad nasal bridge and tip, and narrow jaw. Functional assay in zebrafish larvae showed that Ccnk knockdown resulted in defective brain development, small eyes, and curly spinal cord. These defects were partially rescued by wild-type mRNA coding CCNK but not the mRNA with the identified likely pathogenic variant c.331A>G, supporting a causal role of CCNK variants in neurodevelopmental disorders. Taken together, we reported a syndromic neurodevelopmental disorder with DD/ID and facial characteristics caused by CCNK variations, possibly through a mechanism of haploinsufficiency.

Au–Kline syndrome (AKS, OMIM 616580) is a multiple malformation syndrome, first reported in 2015, associated with intellectual disability. AKS has been associated with de novo loss-of-function variants in HNRNPK (heterogeneous ribonucleoprotein K), and to date, only four of these patients have been described in the literature. Recently, an additional patient with a missense variant in HNRNPK was also reported. These patients have striking facial dysmorphic features, including long palpebral fissures, ptosis, deeply grooved tongue, broad nose, and down-turned mouth. Patients frequently also have skeletal and connective tissue anomalies, craniosynostosis, congenital heart malformations, and renal anomalies. In this report, we describe six new patients and review the clinical information on all reported AKS patients, further delineating the phenotype of AKS. There are now a total of 9 patients with de novo loss-of-function variants in HNRNPK, one individual with a de novo missense variant in addition to 3 patients with de novo deletions of 9q21.32 that encompass HNRNPK. While there is considerable overlap between AKS and Kabuki syndrome (KS), these additional patients demonstrate that AKS does have a distinct facial gestalt and phenotype that can be differentiated from KS. This growing AKS patient cohort also informs an emerging approach to management and health surveillance for these patients.

Cornelia de Lange Syndrome (CdLS) is due to mutations in the genes for the structural and regulatory proteins that make up the cohesin complex, and is considered a cohesinopathy disorder or, more recently, a transcriptomopathy. New phenotypes have been recognized in this expanding field. There are multiple clinical issues facing individuals with all forms of CdLS, particularly in the neurodevelopmental system, but also gastrointestinal, cardiac, and musculoskeletal. Aspects of developmental and cell biology have found common endpoints in the biology of the cohesin complex, with improved understanding of the mechanisms, easier diagnostic tests, and the possibility of potential therapeutics, all major clinical implications for the individual with CdLS. The following abstracts are the presentations from the 7th Cornelia de Lange Syndrome Scientific and Educational Symposium, June 22–23, 2016, in Orlando, FL, in conjunction with the Cornelia de Lange Syndrome Foundation National Meeting. In addition to the scientific and clinical discussions, there were talks related to practical aspects of behavior including autism, transitions, communication, access to medical care, and databases. At the end of the symposium, a panel was held, which included several parents, affected individuals and genetic counselors, and discussed the greatest challenges in life and how this information can assist in guiding future research. The Research Committee of the CdLS Foundation organizes this meeting, reviews, and accepts abstracts, and subsequently disseminates the information to the families through members of the Clinical Advisory Board and publications. AMA CME credits were provided by Greater Baltimore Medical Center, Baltimore, MD.

Cornelia de Lange Syndrome (CdLS), due to mutations in genes of the cohesin protein complex, is described as a disorder of transcriptional regulation. Phenotypes in this expanding field include short stature, microcephaly, intellectual disability, variable facial features and organ involvement, resulting in overlapping presentations, including established syndromes and newly described conditions. Individuals with all forms of CdLS have multifaceted complications, including neurodevelopmental, feeding, craniofacial, and communication. Coping mechanisms and management of challenging behaviors in CdLS, disruption of normal behaviors, and how behavior molds the life of the individual within the family is now better understood. Some psychotropic medications are known to be effective for behavior. Other medications, for example, Indomethacin, are being investigated for effects on gene expression, fetal brain tissue, brain morphology and function in Drosophila, mice, and human fibroblasts containing CdLS-related mutations. Developmental studies have clarified the origin of cardiac defects and role of placenta in CdLS. Chromosome architecture and cohesin complex structure are elucidated, leading to a better understanding of regulatory aspects and controls. As examples, when mutations are present, the formation of loop domains by cohesin, facilitating enhancer-promotor interactions, can be eliminated, and embryologically, the nuclear structure of zygotes is disrupted. Several important genes are now known to interact with cohesin, including Brca2. The following abstracts are from the 8th Cornelia de Lange Syndrome Scientific and Educational Symposium, held in June 2018, Minneapolis, MN, before the CdLS Foundation National Meeting, AMA CME credits provided by GBMC, Baltimore, MD. All studies have been approved by an ethics committee.

Objectives Patients with Cornelia de Lange Syndrome (CdLS) are reported to have conductive (CHL) and sensorineural hearing loss (SNHL), but there is little information pertaining to the progression of hearing loss over time. The goal of this study was to examine the prevalence of CHL and SNHL in adults and children with CdLS and look for changes in SNHL over time. Methods Retrospective chart review of patients with CdLS presenting to a CdLS clinic was conducted. Also, a written survey of clinical concerns was collected from additional patients/families seen in the clinic and through the Cornelia de Lange Foundation. Results Seventy-eight patients (50% female) were included in the chart review. Mean age was 16.8 ± 11.4 years (range-0.6–50 years) and mean age at diagnosis of hearing loss was 4.6 ± 10.6 years (n = 26). Five patients (6.4%) had severe to profound SNHL that improved with time, including 2 who had complete normalization of audiogram results. Thirty-five families/patients completed the clinical survey, and 45.5% of the families reported a noticeable improvement of hearing over time. Conclusions Conductive hearing loss and SNHL are common in CdLS. More than 50% of the patients seen in an adult CdLS clinic reported improvement in hearing loss over time, and a subset of patients had an improvement in SNHL. In light of these findings, we recommend longitudinal evaluations of hearing loss in these patients with both auditory brainstem response and otoacoustic emissions testing if SNHL is identified.

Neurobehavioral and developmental issues with a broad range of deficits are prominent features of Cornelia de Lange syndrome (CdLS), a disorder due to disruption of the cohesin protein complex. The etiologic relationship of these clinical findings to anatomic abnormalities on neuro-imaging studies has not, however, been established. Anatomic abnormalities in the brain and central nervous system specific to CdLS have been observed, including changes in the white matter, brainstem, and cerebellum. We hypothesize that location and severity of brain abnormalities correlate with clinical phenotype in CdLS, as seen in other developmental disorders. In this study, we retrospectively evaluated brain MRI studies of 15 individuals with CdLS and compared these findings to behavior at the time of the scan. Behavior was assessed using the Aberrant Behavior Checklist (ABC), a validated behavioral assessment tool with several clinical features. Ten of fifteen (67%) of CdLS patients had abnormal findings on brain MRI, including cerebral atrophy, white matter changes, cerebellar hypoplasia, and enlarged ventricles. Other findings included pituitary tumors or cysts, Chiari I malformation and gliosis. Abnormal behavioral scores in more than one behavioral area were seen in all but one patient. All 5 of the 15 (33%) patients with normal structural MRI studies had abnormal ABC scores. All normal ABC scores were noted in only one patient and this was correlated with moderately abnormal MRI changes. Although our cohort is small, our results suggest that abnormal behaviors can exist in individuals with CdLS in the setting of relatively normal structural brain findings. © 2016 Wiley Periodicals, Inc.

Cornelia de Lange syndrome (CdLS) is a rare disease characterized by cognitive impairment, multisystemic alterations and premature aging. Furthermore, CdLS cells display gene expression dysregulation and genomic instability. Here, we demonstrated that treatment with antioxidant drugs, such as ascorbic acid and riboceine, reduced the level of genomic instability and extended the in vitro lifespan of CdLS cell lines. We also found that antioxidant treatment partially rescued the phenotype of a zebrafish model of CdLS. Gene expression profiling showed that antioxidant drugs caused dysregulation of gene transcription; notably, a number of genes coding for the zinc finger (ZNF)-containing Krueppel-associated box (KRAB) protein domain (KRAB-ZNF) were found to be downregulated. Taken together, these data suggest that antioxidant drugs have the potential to ameliorate the developmental phenotype of CdLS.

The objective of this study was to explore the factors contributing to quality of life in pediatric patients with non-vascular Ehlers-Danlos syndromes (EDS). Data were analyzed on 41 children with a diagnosis of non-vascular EDS from the de-identified data available from the National Institute on Aging (NIA) study of heritable disorders of connective tissue. Children under age 19 years were seen as part of a long-term evaluation project from 2003 to 2013 on a larger natural history of patients with heritable disorders of connective tissue. Data collected included medical history, physical examination findings, diagnostic study results, and responses on validated questionnaires. We reviewed a sub-cohort of children with a diagnosis of non-vascular EDS and explored pain severity and interference via the Brief Pain Inventory, and sleep quality via the Pittsburgh Sleep Quality Index. Pain severity had a strong correlation with pain interference, and both were similar to other disorders that include chronic pain reported in the literature. Sleep quality did not correlate with pain severity or interference, but all patients had poor sleep quality in comparison to historical controls. We conclude that pain and sleep are significant issues in the pediatric non-vascular EDS population, and future research may be directed toward these issues.

Cornelia de Lange syndrome (CdLS) is a rare multiple malformation syndrome including small stature, distinctive craniofacial features, limb anomalies, neurodevelopmental and behavioral abnormalities, and other organ system pathology. Recent literature has demonstrated that typical CdLS and related overlapping disorders display a broad range of severity and pleiotropy, suggesting that considering these diagnoses as a spectrum may be more appropriate. A molecular basis has been identified in many individuals, with mutations in five genes primarily responsible. These genes encode structural or regulatory proteins of the cohesin protein complex, important in chromatid division, cell cycle function, DNA repair, and epigenetic control. This review summarizes clinical findings, current management recommendations, and recent advances in understanding the underlying biologic mechanisms of these overlapping disorders of cohesin pathology.

Cornelia de Lange Syndrome (CdLS) is the most common example of disorders of the cohesin complex, or cohesinopathies. There are a myriad of clinical issues facing individuals with CdLS, particularly in the neurodevelopmental system, which also have implications for the parents and caretakers, involved professionals, therapists, and schools. Basic research in developmental and cell biology on cohesin is showing significant progress, with improved understanding of the mechanisms and the possibility of potential therapeutics. The following abstracts are presentations from the 6th Cornelia de Lange Syndrome Scientific and Educational Symposium, which took place on June 25-26, 2014, in conjunction with the Cornelia de Lange Syndrome Foundation National Meeting in Costa Mesa, CA. The Research Committee of the CdLS Foundation organizes the meeting, reviews and accepts abstracts, and subsequently disseminates the information to the families through members of the Clinical Advisory Board. In addition to the scientific and clinical discussions, there were educationally focused talks related to practical aspects of behavior and development. AMA CME credits were provided by Greater Baltimore Medical Center, Baltimore, MD.

Although Laird G. Jackson, M.D., has mentored many individuals, most in the field of Medical Genetics, he remains inspirational and true to his basic tenets. This invited comment describes how he shaped the professional course of one of his "mentees." © 2016 Wiley Periodicals, Inc.

Cornelia de Lange syndrome (CdLS) is amultisystemgenetic disorder with distinct facies, growth failure, intellectual disability, distal limb anomalies, gastrointestinal and neurological disease. Mutations in NIPBL, encoding a cohesin regulatory protein, account for >80% of cases with typical facies. Mutations in the core cohesin complex proteins, encoded by the SMC1A, SMC3 and RAD21 genes, together account for ̃5% of subjects, often with atypical CdLS features. Recently, we identified mutations in the X-linked gene HDAC8 as the cause of a small number of CdLS cases. Here, we report a cohort of 38 individuals with an emerging spectrum of features caused by HDAC8 mutations. For several individuals, the diagnosis of CdLS was not considered prior to genomic testing. Most mutations identified are missense and de novo. Many cases are heterozygous females, each with marked skewing of X-inactivation in peripheral blood DNA.Wealso identified eight hemizygous males who are more severely affected. The craniofacial appearance caused by HDAC8 mutations overlaps that of typical CdLS but often displays delayed anterior fontanelle closure, ocular hypertelorism, hooding of the eyelids, a broader nose and dental anomalies, which may be useful discriminating features. HDAC8 encodes the lysine deacetylase for the cohesin subunit SMC3 and analysis of the functional consequences of the missense mutations indicates that all cause a loss of enzymatic function. These data demonstrate that loss-of-function mutations in HDAC8 cause a range of overlapping human developmental phenotypes, including a phenotypically distinct subgroup of CdLS. © The Author 2014. Published by Oxford University Press. All rights reserved.Published by Oxford University Press. All rights reserved.

Mandibulofacial dysostosis with microcephaly (MFDM) is a multiple malformation syndrome comprising microcephaly, craniofacial anomalies, hearing loss, dysmorphic features, and, in some cases, esophageal atresia. Haploinsufficiency of a spliceosomal GTPase, U5-116 kDa/EFTUD2, is responsible. Here, we review the molecular basis of MFDM in the 69 individuals described to date, and report mutations in 38 new individuals, bringing the total number of reported individuals to 107 individuals from 94 kindreds. Pathogenic EFTUD2 variants comprise 76 distinct mutations and seven microdeletions. Among point mutations, missense substitutions are infrequent (14 out of 76; 18%) relative to stop-gain (29 out of 76; 38%), and splicing (33 out of 76; 43%) mutations. Where known, mutation origin was de novo in 48 out of 64 individuals (75%), dominantly inherited in 12 out of 64 (19%), and due to proven germline mosaicism in four out of 64 (6%). Highly penetrant clinical features include, microcephaly, first and second arch craniofacial malformations, and hearing loss; esophageal atresia is present in an estimated ∼27%. Microcephaly is virtually universal in childhood, with some adults exhibiting late "catch-up" growth and normocephaly at maturity. Occasionally reported anomalies, include vestibular and ossicular malformations, reduced mouth opening, atrophy of cerebral white matter, structural brain malformations, and epibulbar dermoid. All reported EFTUD2 mutations can be found in the EFTUD2 mutation database (http://databases.lovd.nl/shared/genes/EFTUD2).

Objective Up to 55% of patients with Cornelia de Lange Syndrome (CdLS) experience sleep disturbance. Prior evaluation of children without CdLS with similar intellectual disability and self-injurious behavior suggests that sleep disturbances may be related to insomnia or circadian issues. Methods Caregivers of 31 patients (19 children) with CdLS completed a sleep history questionnaire focused on sleep patterns and evening sleep behavior to screen for signs and symptoms of insomnia and circadian rhythm disorders. Results The mean age of participants was 14.5 years (range 0.6–37). Major difficulty in falling asleep (75% pediatric, 33% adult) and staying asleep (52% pediatric, 33% adult) was noted. Overall, time to sleep onset was 27.0 ± 17.6 min, however in those with stated sleep onset difficulty, average time to sleep was 37.8 ± 16.4 min (p = 0.002). The mean number of pediatric nighttime awakenings was 1.5 overall and 2.1 in those with stated sleep maintenance difficulties versus 0.7 and 1.5 respectively in adults. Children with CdLS tended to fall back asleep slower (61.8 min) than adults (14.9 min), but none of the comparisons between adult and pediatric sleep measures were significant. Greater than half of participants reported a family member with a possible circadian rhythm disorder. Conclusions Symptoms suggestive of insomnia or circadian rhythm disorder are prevalent in this cohort of children and adults with CdLS. Adults may have less severe symptoms than children, suggesting some improvement over time although this study is underpowered for this analysis. Further studies are necessary to better characterize sleep disturbance in the CdLS population.

Background Joubert syndrome (JS) is a ciliopathy characterised by a distinctive brain malformation (the ‘molar tooth sign’), developmental delay, abnormal eye movements and abnormal breathing pattern. Retinal dystrophy, cystic kidney disease, liver fibrosis and polydactyly are variably present, resulting in significant phenotypic heterogeneity and overlap with other ciliopathies. JS is also genetically heterogeneous, resulting from mutations in 13 genes. These factors render clinical/molecular diagnosis and management challenging. CC2D2A mutations are a relatively common cause of JS and also cause Meckel syndrome. The clinical consequences of CC2D2A mutations in patients with JS have been incompletely reported. Methods Subjects with JS from 209 families were evaluated to identify mutations in CC2D2A . Clinical and imaging features in subjects with CC2D2A mutations were compared with those in subjects without CC2D2A mutations and reports in the literature. Results 10 novel CC2D2A mutations in 20 subjects were identified; a summary is provided of all published CC2D2A mutations. Subjects with CC2D2A -related JS were more likely to have ventriculomegaly (p

Prior studies have suggested that sleep disturbance is common in Cornelia de Lange Syndrome (CdLS); however, the nature of this sleep disturbance has not been well characterized. In this study, we evaluate the prevalence of sleep disordered breathing (SDB) and sleepiness in children and young adults with CdLS.Caregivers of 22 patients with CdLS completed 3 validated Pediatric Sleep Questionnaires: the Pediatric Sleep Questionnaire (PSQ), Pediatric Daytime Sleepiness Scale (PDSS), and OSA18.Both measures of SDB (OSA18 and PSQ) suggest that 35-36% of these patients may have moderate to severe SDB. This is much higher than the general population estimates of 1-4% for SDB with a relative risk of 5.2 (95% CI: 2.8-9.9). Correlation between the OSA18 and PSQ was significant (R=0.67; 95% CI: 0.33-0.85, p=0.0007). Confirming these results among patients with a high probability of SDB (based upon OSA18 scores ≥60), there was a non-significant trend toward increased sleepiness with a relative risk of 2.0 (95% CI: 0.73-5.7, p=0.31) on the PDSS and 2.9 (95% CI: 0.93-9.1, p=0.08) on the PSQ sleepiness scale. In those patients with low probability of SDB (OSA1860), sleepiness was still seen in 13-29% of patients. Overall 23-35% of participants were characterized as sleepy.Sleep disordered breathing and sleepiness appear to be common in CdLS although small sample sizes limit further conclusions. Additional studies with larger sample size and confirmation with polysomnography are needed to further explore the nature and extent of sleep disturbance in this population.

X-linked adrenoleukodystrophy (ALD) is characterized by adrenal insufficiency and neurologic involvement with onset at variable ages. Plasma very long chain fatty acids are elevated in ALD; even in asymptomatic patients. We demonstrated previously that liquid chromatography tandem mass spectrometry measuring C26:0 lysophosphatidylcholine reliably identifies affected males. We prospectively applied this method to 4689 newborn blood spot samples; no false positives were observed. We show that high throughput neonatal screening for ALD is methodologically feasible.

The following abstracts are presentations from the 4th Cornelia de Lange Syndrome Scientific Symposium on June 24, 2010 in conjunction with the Cornelia de Lange Syndrome Foundation National Meeting, Dallas, Texas. This year, an Educational Symposium was added to the program. Cornelia de Lange Syndrome (CdLS) remains the prototype for the cohesinopathy disorders that have been described as having mutations in genes involved in the cohesin subunit in all cells. In addition to clinically related presentations, there were a significant number of developmental and molecular biology-based talks, elucidating the genetic changes and progress towards research for treatment on this condition. A “typical” case presentation is included below as well. AMA CME credits were provided through the University of Texas Southwest. © 2010 Wiley-Liss, Inc.

The cohesin complex has recently been shown to be a key regulator of eukaryotic gene expression, although the mechanisms by which it exerts its effects are poorly understood. We have undertaken a genome-wide analysis of DNA methylation in cohesin-deficient cell lines from probands with Cornelia de Lange syndrome (CdLS). Heterozygous mutations in NIPBL, SMC1A and SMC3 genes account for ∼65% of individuals with CdLS. SMC1A and SMC3 are subunits of the cohesin complex that controls sister chromatid cohesion, whereas NIPBL facilitates cohesin loading and unloading. We have examined the methylation status of 27 578 CpG dinucleotides in 72 CdLS and control samples. We have documented the DNA methylation pattern in human lymphoblastoid cell lines (LCLs) as well as identified specific differential DNA methylation in CdLS. Subgroups of CdLS probands and controls can be classified using selected CpG loci. The X chromosome was also found to have a unique DNA methylation pattern in CdLS. Cohesin preferentially binds to hypo-methylated DNA in control LCLs, whereas the differential DNA methylation alters cohesin binding in CdLS. Our results suggest that in addition to DNA methylation multiple mechanisms may be involved in transcriptional regulation in human cells and in the resultant gene misexpression in CdLS.

Cornelia de Lange Syndrome (CdLS) is a dominantly inherited heterogeneous genetic disorder with multi-system abnormalities. 60% of probands with CdLS have heterozygous mutations in the Nipped-B- like (NIPBL) gene, 5% have mutations in the SMC1A gene, and 1 proband was found to have a mutation in the SMC3 gene. Cohesin is a multi-subunit complex consisting of a SMC1A and SMC3 heterodimer and two non-SMC subunits. SMC1A is located on the human X chromosome and is reported to escape X inactivation. We show that 29 unrelated CdLS probands with 21 unique SMC1A mutations have been identified by our group and others including 7 males. All mutations identified to date are either missense or small deletions with all presumably preserving the protein open reading frame. Both wild type and mutant alleles are expressed. Females quantitatively express twice the amount of SMC1A mRNA as compared to males. The transcriptional profiling of 23 selected genes is different in SMC1A mutant probands, controls and NIPBL mutant probands. These results suggest that mechanistically SMC1A-related CdLS is not due to altered levels of the SMC1A transcript, but rather that the mutant proteins maintain a residual function in males and enact a dominant negative effect in females.

Freeman-Sheldon syndrome, or distal arthrogryposis type 2A (DA2A), is an autosomal dominant condition caused by mutations in MYH3 and characterized by multiple congenital contractures of the face and limbs and normal cognitive development. We identified a subset of five simplex cases putatively diagnosed with “DA2A with severe neurological abnormalities” in which the proband had Congenital Contractures of the LImbs and FAce, Hypotonia, and global Developmental Delay often resulting in early death, a unique condition that we now refer to as CLIFAHDD syndrome. Exome sequencing identified missense mutations in sodium leak channel, nonselective (NALCN) in four families with CLIFAHDD syndrome. Using molecular inversion probes to screen NALCN in a cohort of 202 DA cases as well as concurrent exome sequencing of six other DA cases revealed NALCN mutations in ten additional families with “atypical” forms of DA. All fourteen mutations were missense variants predicted to alter amino acid residues in or near the S5 and S6 pore-forming segments of NALCN, highlighting the functional importance of these segments. In vitro functional studies demonstrated that mutant NALCN nearly abolished the expression of wildtype NALCN, suggesting that mutations that cause CLIFAHDD syndrome have a dominant negative effect. In contrast, homozygosity for mutations in other regions of NALCN has been reported in three families with an autosomal recessive condition characterized mainly by hypotonia and severe intellectual disability. Accordingly, mutations in NALCN can cause either a recessive or dominant condition with varied though overlapping phenotypic features perhaps depending on the type of mutation and affected protein domain(s).

Contains fulltext : 153453.pdf (Publisher’s version ) (Open Access) Intellectual disability (ID) affects approximately 1%-3% of humans with a gender bias toward males. Previous studies have identified mutations in more than 100 genes on the X chromosome in males with ID, but there is less evidence for de novo mutations on the X chromosome causing ID in females. In this study we present 35 unique deleterious de novo mutations in DDX3X identified by whole exome sequencing in 38 females with ID and various other features including hypotonia, movement disorders, behavior problems, corpus callosum hypoplasia, and epilepsy. Based on our findings, mutations in DDX3X are one of the more common causes of ID, accounting for 1%-3% of unexplained ID in females. Although no de novo DDX3X mutations were identified in males, we present three families with segregating missense mutations in DDX3X, suggestive of an X-linked recessive inheritance pattern. In these families, all males with the DDX3X variant had ID, whereas carrier females were unaffected. To explore the pathogenic mechanisms accounting for the differences in disease transmission and phenotype between affected females and affected males with DDX3X missense variants, we used canonical Wnt defects in zebrafish as a surrogate measure of DDX3X function in vivo. We demonstrate a consistent loss-of-function effect of all tested de novo mutations on the Wnt pathway, and we further show a differential effect by gender. The differential activity possibly reflects a dose-dependent effect of DDX3X expression in the context of functional mosaic females versus one-copy males, which reflects the complex biological nature of DDX3X mutations.

The Cornelia de Lange syndrome (CdLS) is a multisystem developmental disorder characterized by facial dysmorphia, upper-extremity malformations, hirsutism, cardiac defects, growth and cognitive retardation, and gastrointestinal abnormalities. Both missense and protein-truncating mutations in NIPBL, the human homolog of the Drosophila melanogaster Nipped-B gene, have recently been reported to cause CdLS. The function of NIPBL in mammals is unknown. The Drosophila Nipped-B protein facilitates long-range enhancer-promoter interactions and plays a role in Notch signaling and other developmental pathways, as well as being involved in mitotic sister-chromatid cohesion. We report the spectrum and distribution of NIPBL mutations in a large well-characterized cohort of individuals with CdLS. Mutations were found in 56 (47%) of 120 unrelated individuals with sporadic or familial CdLS. Statistically significant phenotypic differences between mutation-positive and mutation-negative individuals were identified. Analysis also suggested a trend toward a milder phenotype in individuals with missense mutations than in those with other types of mutations.

We report a 4-year-old female with a de novo complex karyotype with multiple chromosomal rearrangements and a distinctive phenotype. Her medical history is significant for having been a twin born at 35 weeks gestation, breech presentation, with feeding problems and poor growth as an infant, gastroesophageal reflux disease, peripheral pulmonic stenosis, omphalocele, high myopia, and severe mental retardation. She is small for her age with microcephaly, posteriorly sloping forehead, shallow orbits, long palpebral fissures, prominent nose, wide mouth, absent uvula, kyphosis, brachydactyly, bridged palmar crease, and hypertonia. Peripheral blood lymphocytes revealed a karyotype of 46,XX,t(1;12)(p22.3;q21.3),inv(6)(p24q23),t(7;18)(q11.2;q21.2) in all cells. Parental karyotypes and that of her twin were normal. Spectral Karyotyping™ (SKY) and fluorescence in situ hybridization (FISH) with whole chromosome paints for chromosomes 1, 6, 7, 12, and 18 did not reveal additional rearrangements. Prometaphase G-banding analysis suggested that the “inverted” chromosome 6 might contain a cryptic rearrangement. Although no deletion nor duplication was detected using metaphase comparative genomic hybridization (CGH), multicolor high resolution banding (mBAND) demonstrated a double inversion of chromosome 6, resulting in a final karyotype as above but including der(6)(pter → p23::q21 → q22.3::q21 → p23::q22.3 → qter). © 2004 Wiley-Liss, Inc.

Cornelia de Lange syndrome (CdLS) is the prototype for the cohesinopathy disorders that have mutations in genes associated with the cohesin subunit in all cells. Roberts syndrome is the next most common cohesinopathy. In addition to the developmental implications of cohesin biology, there is much translational and basic research, with progress towards potential treatment for these conditions. Clinically, there are many issues in CdLS faced by the individual, parents and caretakers, professionals, and schools. The following abstracts are presentations from the 5th Cornelia de Lange Syndrome Scientific and Educational Symposium on June 20-21, 2012, in conjunction with the Cornelia de Lange Syndrome Foundation National Meeting, Lincolnshire, IL. The research committee of the CdLS Foundation organizes the meeting, reviews and accepts abstracts and subsequently disseminates the information to the families. In addition to the basic science and clinical discussions, there were educationally-focused talks related to practical aspects of management at home and in school. AMA CME credits were provided by Greater Baltimore Medical Center, Baltimore, MD. Report © 2014 Wiley Periodicals, Inc.