Cornelia de Lange syndrome: To diagnose or not to diagnose in utero?

Advancing the Clinical and Molecular Understanding of Cornelia de Lange Syndrome: A Multidisciplinary Pediatric Case Series and Review of the Literature

Cornelia de Lange syndrome (CdLS) is a complex genetic disorder with distinct facial features, growth limitations, and limb anomalies. Its broad clinical spectrum presents significant challenges in pediatric diagnosis and management. Due to cohesin complex mutations, the disorder's variable presentation requires extensive research to refine care and improve outcomes. This article provides a case series review of pediatric CdLS patients alongside a comprehensive literature review, exploring clinical variability and the relationship between genotypic changes and phenotypic outcomes. It also discusses the evolution of diagnostic and therapeutic techniques, emphasizing innovations in genetic testing, including detecting mosaicism and novel genetic variations. The aim is to synthesize case studies with current research to advance our understanding of CdLS and the effectiveness of management strategies in pediatric healthcare. This work highlights the need for an integrated, evidence-based approach to diagnosis and treatment. It aims to fill existing research gaps and advocate for holistic care protocols and tailored treatment plans for CdLS patients, ultimately improving their quality of life.

A Novel de Novo Variant in 5' UTR of the NIPBL Associated with Cornelia de Lange Syndrome

Background: Cornelia de Lange syndrome (CdLS) is a genetic syndrome characterized by intellectual disability, special facial features, growth retardation, feeding difficulties, and multiple organ system abnormalities. NIPBL variants occur in approximately 80% of CdLS cases. Aims: We report a novel de novo heterozygous pathogenic variant in the NIPBL and its association with CdLS. We also examined the key regulatory sequences of the 5′ untranslated region in NIPBL mRNA. Few studies have reported mutation sites in the 5′ untranslated region (UTR) of the NIPBL that result in CdLS. Methods: The patient’s medical history, clinical manifestations, physical examination, laboratory examination, Griffiths development assessment scale—Chinese version, and cardiac B-ultrasound were examined. Mutation screening was conducted using trio whole exome sequencing (trio-WES) and Sanger sequencing. Quantitative PCR was performed to measure the NIPBL expression in peripheral blood mononuclear cells. A Dual-Luciferase reporter assay was conducted to evaluate the transcription of truncated mutants. Results: The proband showed characteristics of CdLS including thick eyebrows, a concave nasal ridge, long and smooth philtrum, downturned corners of the mouth, intellectual disability, postnatal growth retardation, and a short fifth toe. A novel de novo heterozygous pathogenic variant in the NIPBL (c.-467C > T) was identified. A Dual-Luciferase reporter gene assay showed that SPO1 (-490 bp to -360 bp) and SPO3 (-490 bp to -401 bp) induced the highest activity. Conclusions: We found a novel de novo heterozygous pathogenic variant (c.-467C > T) in the NIPBL resulting in CdLS. Our findings expand the spectrum of pathogenic mutations for CdLS. Our in vitro experiments elucidated important regulatory sequences in the 5′ UTR of the NIPBL.

Case Report: Novel NIPBL Variants Cause Cornelia de Lange Syndrome in Chinese Patients

Cornelia de Lange syndrome (CdLS) is a genetic disorder characterized by multisystemic malformations. Mutation in the NIPBL gene accounts for nearly 60% of the cases. This study reports the clinical and genetic findings of three cases of CdLS from unrelated Chinese families. Clinically, all the three cases were classified as classic CdLS based on the cardinal (distinctive facial features and limb malformations) and suggestive (developmental delay, growth retardation, microcephaly, hirsutism, etc.) manifestations. SNP array detected a novel de novo heterozygous microdeletion of 0.2 Mb [arr[GRCh37]5p13.2(36848530_37052821) × 1] that spans the first 43 exons of NIPBL in the fetus with nuchal translucency thickening in case 1. Whole-exome sequencing in family trios plus Sanger sequencing validation identified a de novo heterozygous NIPBL c.5566G>A (p.R1856G) mutation in the fetus with intrauterine growth retardation in case 2 and a novel de novo heterozygous NIPBL c.448dupA (p.S150Kfs^*23) mutation in the proband (an 8-month-old girl) in case 3. The cases presented in this study may serve as references for increasing our understanding of the mutation spectrum of NIPBL in association with CdLS.

Case Report: Prenatal Whole-Exome Sequencing to Identify a Novel Heterozygous Synonymous Variant in NIPBL in a Fetus With Cornelia de Lange Syndrome

Cornelia de Lange syndrome (CdLS) is a genetically heterogeneous disorder characterized by a wide spectrum of abnormalities, including craniofacial dysmorphism, upper limb anomalies, pre- and post-natal growth restrictions, hirsutism and intellectual disability. Approximately 60% of cases are caused by NIPBL variants. Herein we report on a prenatal case presented with bilateral upper-extremity malformations and cardiac defects. Whole-exome sequencing (WES) was performed on the fetus–parental trio and a de novo heterozygous synonymous variant in NIPBL [chr5:37020979; NM_133433.4: c.5328G>A, p. (Gln1776=)] was identified. Reverse transcriptase–polymerase chain reaction (RT–PCR) was conducted to evaluate the potential splicing effect of this variant, which confirmed that the variant caused a deletion of exon 27 (103 bp) by disrupting the splice-donor site and changed the reading frame with the insertion of at least three stop codons. Our finding not only expands the mutation spectrum of NIPBL gene but also establishes the crucial role of WES in searching for underlying genetic variants. In addition, our research raises the important issue that synonymous mutations may be potential pathogenic variants and should not be neglected in clinical diagnoses.

A Broader Perspective on the Prenatal Diagnosis of Cornelia de Lange Syndrome: Review of the Literature and Case Presentation

Cornelia de Lange syndrome (CDLS) is caused by pathogenic variants in genes which are structural or regulatory components of the cohesin complex. The classical Cornelia de Lange (CDLS) phenotype is characterized by distinctive facial features, growth retardation, upper limb reduction defects, hirsutism, and developmental delay. Non-classical phenotypes make this condition heterogeneous. Although CDLS is a heterogeneous clinical and genetic condition, clear diagnostic criteria have been described by specialist consensus. Many of these criteria refer to features that can be seen on prenatal ultrasound. The aim of this paper is twofold: to present the ultrasound findings in fetuses affected by CDLS syndrome; to discuss the recent advances and the limitations in the ultrasound and genetic prenatal diagnosis of CDLS. Our review aims to offer, apart from the data needed to understand the genetics and the prenatal presentation of the disease, a joint perspective of the two specialists involved in the prenatal management of this pathology: the fetal medicine specialist and the geneticist. To better illustrate the data presented, we also include a representative clinical case.

A 16-Day-Old Infant with a Clinical Diagnosis of Classical Cornelia de Lange Syndrome

Cornelia de Lange syndrome (CdLS) is a rare syndromic genetic disorder characterized by multiple congenital anomalies with upper limb reduction defects, along with cardiac, gastrointestinal, and genitourinary defects. It is caused by genetic variations in the chromatin regulator genes, most commonly, the cohesin complex. Even though molecular genetic testing is highly recommended to confirm the diagnosis, high costs and unavailability in some settings are significant setbacks, and clinical criteria could be used. The typical craniofacial features include generalized hirsutism, synophrys, microbrachycephaly, highly arched eyebrows, and long eyelashes, along with height and weight below the 5th percentile. In this paper, we present a case of a 16-day-old male infant in whom a clinical diagnosis of classical CdLS was made.

Chromatinopathies: A focus on Cornelia de Lange syndrome

In recent years, many genes have been associated with chromatinopathies classified as "Cornelia de Lange Syndrome-like." It is known that the phenotype of these patients becomes less recognizable, overlapping to features characteristic of other syndromes caused by genetic variants affecting different regulators of chromatin structure and function. Therefore, Cornelia de Lange syndrome diagnosis might be arduous due to the seldom discordance between unexpected molecular diagnosis and clinical evaluation. Here, we review the molecular features of Cornelia de Lange syndrome, supporting the hypothesis that "CdLS-like syndromes" are part of a larger "rare disease family" sharing multiple clinical features and common disrupted molecular pathways.

Clinical Diagnosis of Classical Cornelia de Lange Syndrome Made From Postmortem Examination of Second Trimester Fetus With Novel NIPBL Pathogenic Variant

Classical Cornelia de Lange syndrome (CdLS) is a rare genetic disorder which is associated with distinctive facial features, growth retardation, significant intellectual disability and global developmental delay, hirsutism, and upper-limb reduction defects. Classical CdLS is associated with pathogenic variants in NIPBL. We present a clinical diagnosis of classical CdLS made in a second trimester male fetus with advanced maceration who had undergone intrauterine death at 15 + 6 weeks gestation. The diagnosis was suspected after multiple congenital anomalies were identified on fetal postmortem examination. These included intrauterine growth retardation, upper limb anomalies, ventricular septal defect and diaphragmatic hernia, and skeletal and genitourinary abnormalities. Related prenatal screening findings included a raised nuchal translucency and low maternal serum pregnancy-associated plasma protein-A. Targeted molecular sequencing of genes associated with CdLS identified a novel de novo frameshift pathogenic variant in NIPBL, which confirmed the diagnosis. This report describes our case and reviews the current literature on prenatal diagnosis of CdLS. In summary, we demonstrate that clinical diagnosis of CdLS in a second trimester fetus, through postmortem examination findings, is possible, with confirmation through molecular testing.

Fetal cardiac abnormalities: Genetic etiologies to be considered

Congenital heart diseases are a common prenatal finding. The prenatal identification of an associated genetic syndrome or a major extracardiac anomaly helps to understand the etiopathogenic diagnosis. Besides, it also assesses the prognosis, management, and familial recurrence risk while strongly influences parental decision to choose termination of pregnancy or postnatal care. This review article describes the most common genetic diagnoses associated with a prenatal finding of a congenital heart disease and a suggested diagnostic process.

A Case of Cornelia de Lange Syndrome: Difficulty in Prenatal Diagnosis

We report a case of Cornelia de Lange syndrome (CdLS) where prenatal diagnosis was not made even with major anomaly. A 33-year-old Japanese woman was referred to our institution at 23 weeks of gestation because of fetal forearm defect. Ultrasound examination revealed short forearms and short humeri and femurs (–2.1 SD). The fetal estimated body weight was 450 g (–1.3 SD). Fetal MRI at 26 weeks of gestation revealed short forearms and hypoplasty of hand fingers. Fetal growth restriction became evident thereafter, leading to intrauterine fetal death occurring at 29 weeks of gestation. A stillbirth baby was of 798 g in body weight and 33.0 cm in length. External examination showed a low hairline, synophrys, low-set ear, hypertrichosis, and smooth long philtrum with thin lips. The neck appeared short and broad. Finally, CdLS was diagnosed. The prenatal diagnosis might be possible as the arm findings were totally characteristic in a small fetus, regardless of whether an overhanging upper lip was identified. Because CdLS is a rare condition, it is important to consider its possibility as a part of differential diagnosis.

Modeling Cornelia de Lange syndrome in vitro and in vivo reveals a role for cohesin complex in neuronal survival and differentiation

Cornelia de Lange syndrome (CdLS), which is reported to affect ∼1 in 10 000 to 30 000 newborns, is a multisystem organ developmental disorder with relatively mild to severe effects. Among others, intellectual disability represents an important feature of this condition. CdLS can result from mutations in at least five genes: nipped-B-like protein, structural maintenance of chromosomes 1A, structural maintenance of chromosomes 3, RAD21 cohesin complex component and histone deacetylase 8 (HDAC8). It is believed that mutations in these genes cause CdLS by impairing the function of the cohesin complex (to which all the aforementioned genes contribute to the structure or function), disrupting gene regulation during critical stages of early development. Since intellectual disorder might result from alterations in neural development, in this work, we studied the role of Hdac8 gene in mouse neural stem cells (NSCs) and in vertebrate (Danio rerio) brain development by knockdown and chemical inhibition experiments. Underlying features of Hdac8 deficiency is an increased cell death in the developing neural tissues, either in mouse NSCs or in zebrafish embryos.

Cornelia De Lange Syndrome In A 4-Year-Old Child From India: Phenotype Description And Role Of Genetic Counseling

INTRODUCTION

Cornelia de Lange syndrome (CdLS) is a congenital disorder marked by distinctive facial features, severe growth restriction, cognitive disability, global developmental delay, and anomalies involving multiple body organs. Majority cases of CdLS are caused due to sporadic mutations in the NIPBL, SMC1A, SMC3, RAD21, or HDAC8 genes, which form/regulate a multiprotein complex called cohesin. Cohesin is required for the separation of sister chromatids during cell division.

CASE REPORT

We present a rare case of a 4-year-old child from India depicting classical features of CdLS. The patient was managed symptomatically by a multidisciplinary team and was requested regular follow-ups.

CONCLUSION

Phenotype description according to ethnicity may help in diagnosing CdLS. A multipronged approach by a team of physicians from various faculties is required for providing comprehensive medical care to patients with CdLS.

Integrating molecular and structural findings: Wnt as a possible actor in shaping cognitive impairment in Cornelia de Lange syndrome

Cornelia de Lange Syndrome (CdLS) is a choesinopathy: a severe genetic disorder caused by mutations in the cohesin complex genes. The phenotype is characterized by typical facial dysmorphism, growth impairment and multiorgan abnormalities including brain alterations. Wnt pathway is known to play a fundamental role in central nervous system development and it has been shown that Wnt pathway is disrupted in CdLS animal models and patients cells. In this review we investigate the possible link between Wnt pathway disruption and brain abnormalities in Cornelia de Lange Syndrome as such molecular impairment could lead to an abnormal embryonic development resulting in brain abnormalities (i.e. microcephaly, cerebellar hypoplasia, abnormal cortical development) in patients with Cornelia de Lange Syndrome.