De Lange Syndrome Research Articles

Genetic causes of isolated and severe fetal growth restriction in normal chromosomal microarray analysis.

To investigate the genetic burden in fetuses with isolated and severe fetal growth restriction (FGR) using Trio whole-exome sequencing (WES) with a normal chromosomal microarray. This retrospective study analyzed WES results of singleton fetuses with isolated and severe FGR, whose estimated fetal weight (EFW) was less than the third percentile by Hadlock formula, in a tertiary center between March 2016 and March 2022. Cases with abnormal chromosomal microarray analysis (CMA) and TORCH results were excluded. Fifty-one fetuses with isolated and severe FGR and negative CMA results underwent Trio-WES. Of all patients, eight (15.7%) were diagnosed with FGR at its early onset (<32 weeks) and showed pathogenic or likely pathogenic variants involving Nipped-B-like protein gene (NIPBL) (n= 3), fibroblast growth factor receptor 3 (n= 1), pyruvate dehydrogenase E1 subunit alpha 1 (n= 1), collagen, type I, alpha 1 (n= 1), superkiller viralicidic activity 2-like (n= 1), and chloride voltage-gated channel (CLCN5) (n= 1). De novo-generated variants were identified in five fetuses, of which two were novel, including c.6983C>A (p. Thr2328Lys) in NIPBL and c.934-1G>T in CLCN5. Genetic disorders involved Cornelia de Lange syndrome and metabolic and skeletal genetic diseases. The present study indicates that Trio-WES can improve effectivity of prenatal diagnoses for isolated and severe FGR in cases with normal CMA results, aiding prenatal genetic counseling and pregnancy management for FGR fetuses.

A Novel Variant in RAD21 in Cornelia De Lange Syndrome Type 4: Case Report and Bioinformatic Analysis.

Cornelia de Lange Syndrome (CdLS) is a rare genetic disorder that affects many organs. The diagnosis of this condition is primarily clinical and it can be confirmed by molecular analysis of the genes known to cause this disease, although about 30% of CdLS patients are without a genetic diagnosis. Here we report clinical and genetic findings of a patient with CdLS type 4, a syndrome of which the clinical features of only 30 patients have been previously described in the literature. The index patient presented with clinical characteristics previously associated with CdLS type 4 (short nose, thick eyebrow, global development delay, synophrys, microcephaly, weight &lt; 2DS, small hands, height &lt; 2DS). She also presented cardiac anomalies, cleft palate and laryngomalacia, which was never described before. The index patient was diagnosed with a novel de novo&amp;nbsp;RAD21 variant (c.1722_1723delTG, p.Gly575SerfsTer2): segregation analysis, bioinformatic analysis, population data and in silico structural modelling indicate the pathogenicity of the novel variant. This report summarizes previously reported clinical manifestations of CdLS type 4 but also highlights new clinical symptoms, which will aid correct counselling of future CdLS type 4 cases.

Clinical Case Reports 1971-1974

In this paper five case reports were presented and include congenital heart disease in de Lange Syndrome, management of growth retardation in steroid dependent asthma, systemic venous anomalies and partial heterotaxia with normal heart, Ebstein’s malformation of the tricuspid valve with atresia, and superior vena caval obstruction in total anomalous pulmonary venous connection. For each case report, clinical, chest x-ray, electrocardiogram and other pertinent findings were presented. This was followed by discussion of etiology, diagnosis, and treatment options, as appropriate.

Early onset developmental and epileptic encephalopathy and Rett-like phenotype in a 15-year-old girl affected by Cornelia de Lange syndrome type 2 due to a SMC1A gene mutation

Developmental and epileptic encephalopathies (DEE) are conditions in which a mutated gene may cause abnormal functioning of the central nervous system, resulting in both encephalopathy and epileptogenesis. We present a case of a girl with a DEE characterized by a Rett-like phenotype in association with febrile and afebrile clusters of focal seizures. The girl presented typical development until the age of 18 months, followed by regression. The first febrile bilateral tonic-clonic seizure was observed at 30 months of age, and the following month seizures recurred in clusters of several episodes per day every 10 days. These seizures were characterized by behavioural arrest, emotional symptoms, head turning, and followed by bilateral tonic-clonic seizures. The administration of valproic acid and levetiracetam led to prolonged seizure control. However, from the age of 7 years, she had monthly recurrent clusters of focal seizures and non-convulsive status epilepticus which occurred at different ages. Brain and spinal cord MRI showed mild non-progressive hemispheric cerebellar atrophy. A next generation sequencing panel for epilepsy identified the de novo splicing mutation c.2973+1G>A of the SMC1A gene.

Clinical and molecular characteristics of Korean children with Cornelia de Lange syndrome

Other SectionsAbstractIntroductionMaterials and MethodsResultsDiscussionSupplemental MaterialsConflict of interestAuthor’s ContributionsFigureTableReference

Functional crosstalk between the cohesin loader and chromatin remodelers

The cohesin complex participates in many structural and functional aspects of genome organization. Cohesin recruitment onto chromosomes requires nucleosome-free DNA and the Scc2-Scc4 cohesin loader complex that catalyzes topological cohesin loading. Additionally, the cohesin loader facilitates promoter nucleosome clearance in a yet unknown way, and it recognizes chromatin receptors such as the RSC chromatin remodeler. Here, we explore the cohesin loader-RSC interaction. Amongst multi-pronged contacts by Scc2 and Scc4, we find that Scc4 contacts a conserved patch on the RSC ATPase motor module. The cohesin loader directly stimulates in vitro nucleosome sliding by RSC, providing an explanation how it facilitates promoter nucleosome clearance. Furthermore, we observe cohesin loader interactions with a wide range of chromatin remodelers. Our results provide mechanistic insight into how the cohesin loader recognizes, as well as influences, the chromatin landscape, with implications for our understanding of human developmental disorders including Cornelia de Lange and Coffin-Siris syndromes.

Establishment of a transgene-free iPS cell line (SDQLCHi046-A) from a young patient bearing a HDAC8 mutation and suffering from Cornelia de Lange Syndrome

In this study, peripheral blood mononuclear cells were isolated from a young male patient bearing a histone deacetyl-lase 8 (HDAC8) mutation and suffering from Cornelia de Lange Syndrome verified by clinical and genetic diagnosis. Induced pluripotent stem cells (iPSCs) were established by a non-integrative method, using plasmids carrying OCT4, SOX2, KLF4, BCL-XL and C-MYC. The established iPSCs presented typical pluripotent cells morphology, and expressed pluripotent stem cell markers at the mRNA and protein level. The iPSCs also showed differentiative capacity in vitro, and a normal karyotype. In addition, the established iPSCs still carried the HDAC8 mutation observed in the donor tissue.

Decreasing Wapl dosage partially corrects embryonic growth and brain transcriptome phenotypes in Nipbl+/- embryos.

Cohesin rings interact with DNA and modulate the expression of thousands of genes. NIPBL loads cohesin onto chromosomes, and WAPL takes it off. Haploinsufficiency for NIPBL causes a developmental disorder, Cornelia de Lange syndrome (CdLS), that is modeled by Nipbl+/- mice. Mutations in WAPL have not been shown to cause disease or gene expression changes in mammals. Here, we show dysregulation of >1000 genes in WaplΔ/+ embryonic mouse brain. The patterns of dysregulation are highly similar in Wapl and Nipbl heterozygotes, suggesting that Wapl mutations may also cause human disease. Since WAPL and NIPBL have opposite effects on cohesin's association with DNA, we asked whether decreasing Wapl dosage could correct phenotypes seen in Nipbl+/- mice. Gene expression and embryonic growth are partially corrected, but perinatal lethality is not. Our data are consistent with the view that cohesin dynamics play a key role in regulating gene expression.

Cornelia de Lange syndrome

The article presents the results of dynamic monitoring of a patient with Cornelia de Lange syndrome. The patient was born with archetypal facial features, multiple stigmas of dysembriogenesis, pre– and postnatal growth retardation and perinatal pathology of the brain in the form of spastic tetraparesis. Later, the child progressed with psychomotor development delay, hearing and vision disorders. Based on the conducted examination, consultations of specialists, including genetics, the diagnosis of «Cornelia de Lange syndrome» was established. To make this diagnosis, specific facial features in combination with additional criteria are sufficient.

The developmental trajectories of the behavioral phenotype and neuropsychiatric functioning in Cornelia de Lange and Rubinstein Taybi syndromes: A longitudinal study.

Several changes in the behavioral phenotype arise with the growth of children affected by Cornelia de Lange Syndrome (CdLS) and Rubinstein-Taybi Syndrome (RSTS). However, previous research relied on a cross-sectional study design turning into age-related comparisons of different syndromic cohorts to explore age-dependent changes. We aim to outline the variating pathways of the neuropsychiatric functioning across the lifespan in CdLS and RSTS, through the setting up of a longitudinal study design. The sample included 14 patients with CdLS and 15 with RSTS. The assessments were carried out in two different timepoints. Our findings highlight that the cognitive profile of CdLS is subjected to a worsening trend with decreasing Intellectual Quotient (IQ) scores from T0 to T1, whereas RSTS shows a stable IQ over time. Patients affected by RSTS show greater improvements compared to CdLS in communication, daily living skills, social abilities, and motor skills across the lifespan. Both syndromes report an upward trend in behavioral and emotional difficulties even if CdLS exhibit a significant and major deterioration compared to individuals with RSTS. Being aware of the early dysfunctional patterns which might pave the way for later neuropsychiatric impairments is the first step for planning preventive interventions.

Microdeletions at 19p13.11p12 in five individuals with neurodevelopmental delay

Only few copy number variants at chromosome 19p13.11 have been reported, thus associated clinical information is scarce. Proximal to these copy number losses, we now identified deletions in five unrelated individuals with neurodevelopmental disorders. They presented with psychomotor delay as well as behavioral and sleeping disorders, while complex cardiovascular, skeletal, and various other malformations were more variable. Dysmorphic features were rather unspecific and not considered as a recognizable gestalt.Neither of the analyzed parents carried their offsprings' deletions, indicating de novo occurrence. The deletion sizes ranged between 0.7 and 5.2 Mb, were located between 18 and 24 megabases from the telomere, and contained a variable number of protein-coding genes (n = 25–68). Although not all microdeletions shared a common region, the smallest common overlap of some of the deletions provided interesting insights in the chromosomal region 19p13.11p12. Diligent literature review using OMIM and Pubmed did not identify a satisfying candidate gene for neurodevelopmental disorders. In the literature, a de novo in-frame deletion in MAU2 was considered pathogenic in an individual with Cornelia de Lange syndrome. Therefore, the clinical differential diagnosis of this latter syndrome in one individual and the encompassment of MAU2 in three individuals' deletions suggest clinical and genetic overlap with this specific syndrome. Three of the four here reported individuals with deletion encompassing GDF1 had different congenital heart defects, suggesting that this gene's haploinsufficiency might contribute to the cardiovascular phenotype, however, with reduced penetrance.Our findings indicate an association of microdeletions at 19p13.11/ 19p13.11p12 with neurodevelopmental disorders, variable symptoms, and malformations, and delineate the phenotypic spectrum of deletions within this genomic region.

Cornelia de Lange Syndrome: A Case Report with a Novel Congenital Heart Disease Association

Introduction: Cornelia de Lange syndrome (CdLS) is a rare non-hereditary syndrome. The key diagnosis is unique facial features, limb anomalies, and growth retardation. Cardiac defects with gastrointestinal and genitourinary anomalies may be associated. Case Presentation: This is a case of neonatal CdLS that we think is interesting due to its association with a novel congenital heart complex. Conclusions: Patients with CdLS have a high incidence of congenital heart disease (CHD), so a cardiologic study of all of these patients is suggested.

Pathological Role of HDAC8: Cancer and Beyond.

Histone deacetylase 8 (HDAC8) is a class I HDAC that catalyzes the deacetylation of histone and non-histone proteins. As one of the best-characterized isoforms, numerous studies have identified interacting partners of HDAC8 pertaining to diverse molecular mechanisms. Consequently, deregulation and overexpression of HDAC8 give rise to diseases. HDAC8 is especially involved in various aspects of cancer progression, such as cancer cell proliferation, metastasis, immune evasion, and drug resistance. HDAC8 is also associated with the development of non-cancer diseases such as Cornelia de Lange Syndrome (CdLS), infectious diseases, cardiovascular diseases, pulmonary diseases, and myopathy. Therefore, HDAC8 is an attractive therapeutic target and various HDAC8 selective inhibitors (HDAC8is) have been developed. Here, we address the pathological function of HDAC8 in cancer and other diseases, as well as illustrate several HDAC8is that have shown anti-cancer effects.

Efficacy of congenital heart disease transition clinics in improving patient education

Abstract Background Less than one third of adolescents with congenital heart disease (CHD) successfully complete a structured transition to adult care. Patient education is at the centre of the transition process, however, data on the impact of transition visits are limited. Purpose To assess the efficacy of our transition clinic in educating adolescents with CHD about their cardiac condition in preparation for adult CHD care. Methods All patients seen in our transition clinic between April 2015 and January 2022 were included. Integrated care pathways designed by the Pan London Transition Consortium guided us in the assessment and education during each of the 3 pre-planned transition visits (“ready, steady and go” model). Data collected included demographic and clinical characteristics, and qualitative assessment of the following categories: understanding, naming and describing their cardiac condition, adherence to and involvement in medication management, self-reported anxiety and awareness of the importance of dental hygiene. Results A total of 611 patients were included in the study (age 15.1±2.3 years at the first visit, 48.1% female). 51.1% of patients attended 2 and 19.3% 3 transition consultations. Most adolescents (52.5%) had CHD of moderate complexity, whereas 28.5% had simple defects and 19% severe complexity. Learning disability (LD) was present in 19% of cases, of which 35.3% were genetic syndromes (21.6% Down Syndrome, 8.6% DiGeorge Syndrome, 2.6% Noonan Syndrome, 1.9% Sotos Syndrome, 0.9% Asperger Syndrome, 0.9% Cornelia De Lange Syndrome). The overall comprehension of their condition increased significantly in patients without LD at the second (good or excellent understanding: from 20.9% to 60.2%, p&amp;lt;0.0001; naming: from 19.8% to 50.2%, p&amp;lt;0.0001; describing: from 13.9% to 40.2%, p&amp;lt;0.0001) and third visit (understanding: 66.7%, p=0.043; naming: 60.4%, p=0.004, describing: 56.3%, p=0.002; Table 1). Patients with LD did not improve their knowledge over time in understanding, naming, and describing their condition between the first and second and second and third visits (all p&amp;gt;0.05). Adherence to and the involvement in medication management, the self-reported anxiety and awareness of the importance of dental care did not change over time (Figure 1). Conclusions A structured transition program is an important tool in educating and supporting the delivery of care for CHD adolescents and their families prior their transition into the adult care. Our transition programme had a positive impact on comprehension in the majority of children. Adolescents with learning difficulties are a group who may benefit from more intensive or individually tailored education during transition to ensure that they are supported to understand their health needs and empowered to make their own choices where possible. Funding Acknowledgement Type of funding sources: None.

Pathogenic variants detected by RNA sequencing in Cornelia de Lange syndrome

Recent studies suggest that transcript isoforms significantly overlap (approximately 60%) between brain tissue and Epstein–Barr virus-transformed lymphoblastoid cell lines (LCLs). Interestingly, 14 cohesion-related genes with variants that cause Cornelia de Lange Syndrome (CdLS) are highly expressed in the brain and LCLs. In this context, we first performed RNA sequencing of LCLs from 22 solved (with pathogenic variants) and 19 unsolved (with no confirmed variants) CdLS cases. Next, an RNA sequencing pipeline was developed using solved cases with two different methods: short variant analysis (for single-nucleotide and indel variants) and aberrant splicing detection analysis. Then, 19 unsolved cases were subsequently applied to our pipeline, and four pathogenic variants in NIPBL (one inframe deletion and three intronic variants) were newly identified. Two of three intronic variants were located at Alu elements in deep-intronic regions, creating cryptic exons. RNA sequencing with LCLs was useful for identifying hidden variants in exome-negative cases.

Treatment of Cornelia de Lange syndrome: Evidence-based medicine and expert opinion

Background: Cornelia de Lange syndrome is a rare genetic condition of highly variable phenotype making ranging from classic syndrome with many cardinal features to mild syndrome with less characteristic features. Materials and methods: The mother of a three and half years old boy brought her son to our clinic because of significant developmental delay and over-activity. The mother denied the presence of relevant family history. Results: The boy was mentally retarded and had facial dysmorphic features including thick eyebrows with synophrys, long or smooth philtrum, thin upper lip vermilion, and low set ears. The boy poor adaptive skills and has not achieved urine and bowel control and was unable to hold spoon appropriately to feed himself. He had no speech development and was not saying any word. At the clinic, he was very active, but he was responding to name and had acceptable eye contact and therefore, he was not considered to have autistic features. It was not possible to convince him to take a pen to scribble. Based on our extensive published experiences with treatment of mental retardation syndrome, we recommended an initial therapeutic course which included a course of intramuscular piracetam 600 mg given daily in the morning every third day (Ten doses over one month). Conclusion: An expert therapeutic recommendation for the condition is described.

Treatment of Cornelia de Lange syndrome: Evidence-based medicine and expert opinion

Background: Cornelia de Lange syndrome is a rare genetic condition of highly variable phenotype making ranging from classic syndrome with many cardinal features to mild syndrome with less characteristic features. Materials and methods: The mother of a three and half years old boy brought her son to our clinic because of significant developmental delay and over-activity. The mother denied the presence of relevant family history. Results: The boy was mentally retarded and had facial dysmorphic features including thick eyebrows with synophrys, long or smooth philtrum, thin upper lip vermilion, and low set ears. The boy poor adaptive skills and has not achieved urine and bowel control and was unable to hold spoon appropriately to feed himself. He had no speech development and was not saying any word. At the clinic, he was very active, but he was responding to name and had acceptable eye contact and therefore, he was not considered to have autistic features. It was not possible to convince him to take a pen to scribble. Based on our extensive published experiences with treatment of mental retardation syndrome, we recommended an initial therapeutic course which included a course of intramuscular piracetam 600 mg given daily in the morning every third day (Ten doses over one month). Conclusion: An expert therapeutic recommendation for the condition is described.

Deep intronic NIPBL de novo mutations and differential diagnoses revealed by whole genome and RNA sequencing in Cornelia de Lange syndrome patients.

Cornelia de Lange syndrome (CdLS; MIM# 122470) is a rare developmental disorder. Pathogenic variants in 5 genes explain approximately 50% cases, leaving the other 50% unsolved. We performed whole genome sequencing (WGS) ± RNA sequencing (RNA-seq) in 5 unsolved trios fulfilling the following criteria: (i) clinical diagnosis of classic CdLS, (ii) negative gene panel sequencing from blood and saliva-isolated DNA, (iii) unaffected parents' DNA samples available and (iv) proband's blood-isolated RNA available. A pathogenic de novo mutation (DNM) was observed in a CdLS differential diagnosis gene in 3/5 patients, namely POU3F3, SPEN, and TAF1. In the other two, we identified two distinct deep intronic DNM in NIPBL predicted to create a novel splice site. RT-PCRs and RNA-Seq showed aberrant transcripts leading to the creation of a novel frameshift exon. Our findings suggest the relevance of WGS in unsolved suspected CdLS cases and that deep intronic variants may account for a proportion of them.

Phenotypes of Cornelia de Lange syndrome caused by non-cohesion genes: Novel variants and literature review.

BackgroundCornelia de Lange syndrome (CdLS) is a genetic disorder caused by variants in cohesion genes including NIPBL, SMC1A, SMC3, RAD21, and HDAC8. According to the 2018 consensus statement, a patient with clinical scored ≥ 11 points could be diagnosed as CdLS. However, some variants in non-cohesion genes rather than cohesion genes can manifest as phenotypes of CdLS.ObjectivesThis study describes six variants of non-cohesion genes (KDM6A, KMT2D, KMT2A ANKRD11, and UBE2A), and assesses the reliability of 11-points scale criteria in the clinical diagnosis of CdLS.MethodsWhole-exome sequencing (WES) was performed on six patients with features of CdLS. Phenotypic and genotypic spectra of 40 previously reported patients with features of CdLS caused by non-cohesion genes variants and 34 previously reported patients with NIPBL variants were summarized. Clinical score comparison among patients with NIPBL variants versus those with variants in non-cohesin genes was performed.ResultsVariants in non-cohesion genes were found in six patients [KMT2A (n = 2), KMT2D, ANKRD11, KDM6A, and UBE2A]. Of them, four variants (KMT2A c.7789C > T, ANKRD11 c.1757_1776del, KDM6A c.655-1G > A, and UBE2A c.439C > T) were novel. Combining with previously reported cases, 46 patients with phenotypes of CdLS caused by variants in 20 non-cohesion genes are now reported. From this total cohort, the average clinical score of patients in ANKRD11 cohort, SETD5 cohort, and AFF4 cohort was statistically lower than those in NIPBL cohort (8.92 ± 1.77 vs. 12.23 ± 2.58, 7.33 ± 2.52 vs. 12.23 ± 2.58, 5.33 ± 1.53 vs. 12.23 ± 2.58; p < 0.05). The average clinical score of KMT2A cohort, EP300 cohort, and NIPBL cohort had not significantly different from (11 ± 2.19 vs. 12.23 ± 2.58, 10 ± 4.58 vs. 12.23 ± 2.58; p > 0.05).ConclusionWe described 4 novel variants of non-cohesion genes in six Chinese patients with phenotypes of CdLS. Of note, three genes (KMT2D, KDM6A, and UBE2A) causing features of CdLS have never been reported. The proposed clinical criteria for CdLS needed to be updated and refined, insofar as WES was necessary to confirm the diagnosis of CdLS. Our study expanded the spectra of non-cohesion genetic variations in patients with features of CdLS.

Establishment of a human induced pluripotent stem cell line, KMUGMCi002-A, from a patient bearing a heterozygous c.6362_6364del mutation in the NIPBL gene leading Cornelia de Lange syndrome (CdLS)

Cornelia de Lange syndrome (CdLS) is a multiple congenital anomalies syndrome caused by mutations in the cohesion complex. The mutations in NIPBL, one of cohesion regulatory proteins, are the most frequent cause of CdLS. The peripheral blood mononuclear cells (PBMCs) from a patient carrying a heterozygous 3 bp deletion in Exon 37 of the NIPBL gene were reprogrammed using the CytoTune-iPS2.0 Sendai Reprogramming Kit. The deleted mutation in NIPBL will cause the abnormal truncated protein, which is known to associated with CdLS. The established human induced pluripotent cell (hiPSC) line will enable proper in vitro disease modelling of CdLS.Resource Table: