Familial Brachmann-de Lange syndrome: further evidence for autosomal dominant inheritance and review of the literature

Diagnosis and management of Cornelia de Lange syndrome: first international consensus statement

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.

NIPBL expression levels in CdLS probands as a predictor of mutation type and phenotypic severity

Cornelia de Lange syndrome (CdLS) is a rare, genetically heterogeneous multisystem developmental disorder with a high degree of variability in its clinical presentation. Approximately 65% of probands harbor mutations in genes that encode core components (SMC1A, SMC3, and RAD21) or regulators (NIPBL, HDAC8) of the cohesin complex, of which mutations in NIPBL are the most common. Cohesin plays a canonical role in sister chromatid cohesion during cell division and non-canonical roles in DNA repair, stem cell maintenance and differentiation, and regulation of gene expression. Disruption of the latter role seems to be the major contributor to the underlying molecular pathogenesis of CdLS. NIPBL is required for loading and unloading the cohesin complex onto chromosomes. The expression levels of NIPBL itself appear to be tightly regulated and highly evolutionarily conserved. Droplet digital PCR was used to quantify NIPBL mRNA expression levels with high precision from a cohort of 37 samples (NIPBL, SMC1A, SMC3, and HDAC8 mutation positive probands and negative control). Probands with severe forms of CdLS or severe mutation types were found to have lower levels of NIPBL in comparison to phenotypically milder patients and controls. Levels of NIPBL also correlated with the presence of mutations in different CdLS-causing genes. The data suggests that NIPBL levels are closely correlated with the severity of CdLS and with specific causative genes and types of mutations. ddPCR may provide a tool to assist in diagnostic approaches to CdLS, for genetic counseling and prognosis, and for monitoring potential therapeutic modalities in the future. © 2016 Wiley Periodicals, Inc.

The behavioural phenotype of Cornelia de Lange Syndrome: a study of 56 individuals

BACKGROUND

Few studies have investigated functional and behavioural variables of Cornelia de Lange Syndrome (CdLS) in a large sample of individuals. The aim of this study is to provide greater insight into the clinical, behavioural and cognitive characteristics that are associated with CdLS.

METHODS

In total, 56 individuals with CdLS participated in the study. During hospitalization, their mothers received a number of questionnaires to complete. The behavioural phenotype was investigated using the following scales: Developmental Behaviour Scale Primary Carer Version; Autism Behaviour Checklist; Childhood Autism Rating Scale.

RESULTS

Our participants demonstrated some behavioural characteristics that are frequently associated with CdLS (hyperactivity, attention disorder, anxiety, compulsive disorders, self-injurious behaviour and autistic-like features). Our findings demonstrate the variability of behavioural characteristics in CdLS in addition to highlighting the contribution of some variables to both the CdLS behavioural profile and the developmental trajectory of the behavioural pattern.

CONCLUSIONS

The behavioural characteristics identified in our sample were correlated with some clinical and functional aspects (chronological age, cognitive level and clinical phenotype). The variability of the behavioural profile in CdLS reflected the wide variability in cognitive and adaptive functioning across individuals and led us to conclude that there may be multiple behavioural phenotypes associated with the syndrome. Further comparative studies between CdLS and individuals with intellectual disability or other genetic syndromes may help to provide further understanding of the behavioural phenotype of CdLS.

Neuropsychological rehabilitation in a case of Cornelia de Lange syndrome

Cornelia de Lange syndrome is a rare congenital disorder. Symptoms include a characteristic facial structure, pre- and post-natal growth deficiency, hypertrichosis, and visceral and cardiovascular anomalies. Behavioural problems and moderate to severe mental retardation are also present. In this paper, we report a mild case of Cornelia de Lange syndrome. The neuropsychological rehabilitation of this patient is also described. It was structured on the patient's specific areas of strength and weakness in order to facilitate the development of adaptive cognitive abilities. To maximise the learning potential of these children, we recommend specific interventions with a multidimensional neuropsychological approach, which considers developmental abilities and disabilities as related to the global reality of the child.

NIPBL mutational analysis in 120 individuals with Cornelia de Lange syndrome and evaluation of genotype-phenotype correlations

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.

An Irish three-generation family of Cornelia de Lange syndrome displaying autosomal dominant inheritance

The existence of familial de Lange syndrome has been documented in sibs and in parent-child families, but the inheritance pattern continues to be the cause of much debate. We describe a classically affected neonate with de Lange syndrome, an affected mother and probably affected maternal grandmother. These cases show evidence for a dominantly inherited syndrome with a de Lange phenotype.

Cornelia de Lange syndrome: a case study

Cornelia de Lange syndrome (CdLS) is a rare dysmorphogenic disorder characterized by growth retardation, severe cognitive limitations, distinctive facial features, and limb reduction anomalies recognizable at birth. Currently, no single criterion is diagnostic for CdLS, and misdiagnosis is not uncommon. Long-term management of the infant with CdLS requires a coordinated effort among many different specialists. This article presents a general overview of Cornelia de Lange syndrome. It concludes with a case study illustrating the many problems infants with CdLS may have and the great amount of teaching and support that is needed by families affected by CdLS.

Dominant paternal transmission of Cornelia de Lange syndrome: a new case and review of 25 previously reported familial recurrences

The Cornelia de Lange syndrome (CdLS) is an autosomal dominant multisystem disorder characterized by somatic and cognitive retardation, characteristic facial features, limb abnormalities, hearing loss, and other organ system involvement. The vast majority of cases (99%) are sporadic, with rare familial occurrences having been reported. Most individuals with CdLS do not reproduce as a result of the severity of the disorder. Maternal transmission has been well documented, as have several cases of multiple-affected children being born to apparently unaffected parents. Paternal transmission has rarely been reported. A case is reported here of a father with classic features of CdLS with a similarly affected daughter. A review of the reported familial cases of CdLS is summarized.

Brachmann-de Lange syndrome: a cause of early symmetric fetal growth delay

Brachmann-de Lange syndrome is characterized by pre- and postnatal growth retardation, microbrachycephaly, hirsutism, various visceral and limb anomalies and a typical face. A sonographic prenatal diagnosis at mid-trimester is reported in a case of severe, symmetrical fetal growth delay at 20 weeks gestation, with a thickened skin on the forehead, a small nose and a marked depressed nasal bridge, a long philtrum, micrognathia and a persistently flexed right forearm, with a single bone associated to oligodactyly. Due to the severe mental impairment with a commonly estimated intelligence quotient under 60, the pregnancy was terminated after parental consent.

Brachmann-de Lange syndrome: autosomal dominant inheritance and male-to-male transmission

We report on familial occurrence of the Brachmann-de Lange syndrome (BDLS): a mildly affected father and his severely affected son and daughter who have different mothers. Both children are severely affected while the father has a much milder but definite BDLS phenotype. Our report documents the third example of male-to-male transmission and adds to the argument against exclusively maternal transmission in familial cases. In addition, our findings illustrate the occurrence of severe manifestations in cases of familial BDLS.

Autosomal dominant inheritance of Brachmann-de Lange syndrome

A mother with mild phenotype and her severely affected son, both with classic manifestations of Brachmann-de Lange syndrome (BDLS), are described. This documented mother-to-child transmission supports the hypothesis of autosomal dominant transmission with intrafamilial variability. Known cases of BDLS with autosomal dominant inheritance are reviewed. Although most cases of BDLS are sporadic, a careful evaluation of parents of affected children is important for appropriate genetic counseling.

Identical twin discordance for the Brachmann-de Lange syndrome revisited

The only known twin pair evidently discordantly affected for the BDLS (Brachmann-de Lange syndrome) and who had been considered monozygotic (MZ) based on blood analysis remained a problem because biological zygosity determination needed further typing. In this report we review the clinical findings of this pair of twins at the age of 20. The use of DNA fingerprinting with three multilocus probes, F10, DNF24, and 33.6, allowed us to present evidence of monozygosity with a high degree of certainty. The significance of this confirmation of discordance in determining the cause of BDLS is discussed. Intensive comparative genomic studies of the discordant twin sisters may be useful to unravel the molecular genetics of this enigmatic pattern of malformation.

Brachmann-de Lange syndrome: pre- and postnatal findings

Brachmann-de Lange syndrome (BDLS) is a well-delineated and relatively common syndrome. However, prenatal diagnosis has never been reported, even if in some cases ultrasonography demonstrated one or more manifestations of the syndrome. We report on 3 cases: in the first 2 cases, prenatal ultrasonography demonstrated some signs of the condition. The third represents, to our knowledge, the first prenatal diagnosis of BDLS. We also present a review of the literature concerning pre- and postnatal findings in this syndrome.

A further report of Brachmann-de Lange syndrome in two sibs with normal parents

We report on a family in which a girl and a boy in the same sibship show variable manifestations of a less severe type of Brachmann-de Lange syndrome without significant prenatal growth deficiency and reduction deformities of the forearms. Both parents are healthy and phenotypically normal, and no other family members are affected. All the affected sibs except one described so far with normal parents presented the severe type of Brachmann-de Lange syndrome (now sometimes classified as type I: "classic" or "full" Brachmann-de Lange syndrome), with major upper limb anomalies, severe growth and mental retardation and, frequently, early death. We discuss the possible role of genomic imprinting in the etiology of this syndrome.

Male-to-male transmission of mild Brachmann-de Lange syndrome

We report on a father and son with mild Brachmann-de Lange syndrome. Previous reports have documented apparent autosomal dominant transmission; however, only one example of male-to-male transmission of possible Brachmann-de Lange syndrome has been reported. This case provides further evidence of the existence of an autosomal dominant form of Brachmann-de Lange syndrome.