Prenatally diagnosed omphaloceles: Report of 92 cases and association with Beckwith-Wiedemann syndrome.

Objective: Describe the prevalence, perinatal and long-term outcomes of Beckwith-Wiedemann syndrome (BWS) among prenatally detected omphaloceles.

Methods: All prenatally diagnosed omphaloceles from 2010 to 2015 within a single tertiary care centre were identified. An echocardiogram and detailed fetal ultrasound were performed, and amniocentesis was offered with karyotype/microarray analysis and BWS molecular testing.

Wilms tumour in Beckwith-Wiedemann Syndrome and loss of methylation at imprinting centre 2: revisiting tumour surveillance guidelines.

Beckwith-Wiedemann Syndrome (BWS) is an overgrowth syndrome caused by a variety of molecular changes on chromosome 11p15.5. Children with BWS have a significant risk of developing Wilms tumours with the degree of risk being dependent on the underlying molecular mechanism.

Genomic imbalance in the centromeric 11p15 imprinting center in three families: Further evidence of a role for IC2 as a cause of Russell-Silver syndrome.

Russell-Silver syndrome is a heterogeneous disorder characterized by intrauterine growth retardation, postnatal growth deficiency, characteristic facial appearance, and other variable features. Genetic and epigenetic alterations are identified in about 60% of individuals with Russell-Silver syndrome. Most frequently, Russell-Silver syndrome is caused by altered gene expression on chromosome 11p15 due to loss of methylation at the telomeric imprinting center.

Complex genomic rearrangements in the dystrophin gene due to replication-based mechanisms.

Genomic rearrangements such as intragenic deletions and duplications are the most prevalent type of mutations in the dystrophin gene resulting in Duchenne and Becker muscular dystrophy (D/BMD). These copy number variations (CNVs) are nonrecurrent and can result from either nonhomologous end joining (NHEJ) or microhomology-mediated replication-dependent recombination (MMRDR). We characterized five DMD patients with complex genomic rearrangements using a combination of MLPA/mRNA transcript analysis/custom array comparative hybridization arrays (CGH) and breakpoint sequence analysis to investigate the mechanisms for these rearrangements.

Does integration of various ion channel measurements improve diagnostic performance in cystic fibrosis?

Rationale: The diagnosis of cystic fibrosis (CF) may remain inconclusive despite comprehensive evaluation.

Objectives: Determine whether combined ion channel measurements (C-ICMs) obtained from different end-organ epithelia can help diagnose CF.

Methods: Prospective enrollment of (1) a training sample of 156 non-CF subjects and 107 patients with CF, and (2) a validation cohort of 202 patients with single-organ CF-like phenotypes.

Does extensive genotyping and nasal potential difference testing clarify the diagnosis of cystic fibrosis among patients with single-organ manifestations of cystic fibrosis?

Background: The phenotypic spectrum of cystic fibrosis (CF) has expanded to include patients affected by single-organ diseases. Extensive genotyping and nasal potential difference (NPD) testing have been proposed to assist in the diagnosis of CF when sweat testing is inconclusive. However, the diagnostic yield of extensive genotyping and NPD and the concordance between NPD and the sweat test have not been carefully evaluated.

Combined de-novo mutation and non-random X-chromosome inactivation causing Wiskott-Aldrich syndrome in a female with thrombocytopenia.

Objective: Disorders linked to mutations in the X chromosomes typically affect males. The aim of the study is to decipher the mechanism of disease expression in a female patient with a heterozygous mutation on the X-chromosome.

Patients And Methods: Clinical data was extracted from the Canadian Inherited Marrow Failure Registry.

Mosaicism for genome-wide paternal uniparental disomy with features of multiple imprinting disorders: diagnostic and management issues.

Mosaicism for genome-wide paternal uniparental disomy (UPD) has been reported in only seven live born individuals to date. Clinical presentation includes manifestations of multiple paternal UPD syndromes with high variability, likely due to the variable levels of mosaicism in different somatic tissues. We report an eighth case in a female patient with mosaicism for genome-wide paternal UPD which highlights the complex clinical presentation.

Severe presentation of Beckwith-Wiedemann syndrome associated with high levels of constitutional paternal uniparental disomy for chromosome 11p15.

Beckwith-Wiedemann syndrome (BWS) is an overgrowth syndrome characterized by macrosomia, macroglossia, omphalocele, hemihyperplasia, and increased tumor risk. BWS can be associated with genetic and/or epigenetic alterations that modify imprinted gene expression on chromosome 11p15.5.

Constitutional UPD for chromosome 11p15 in individuals with isolated hemihyperplasia is associated with high tumor risk and occurs following assisted reproductive technologies.

Isolated hemihyperplasia (IH) refers to a distinct diagnosis involving asymmetric overgrowth of single or multiple organs or regions of the body and can result from various genomic changes including molecular alterations of 11p15; these are paternal uniparental disomy (UPD), and alterations of methylation at two imprinting centers at 11p15: IC1 (H19) and IC2 (KCNQ1OT1). As little information is available on the molecular basis of tumor development in IH, or on the frequency of tumors in children with different molecular subtypes of IH, molecular testing was undertaken on 51 patients with IH and revealed: 8 (16%) with UPD, 3 (6%) with hypomethylation at KCNQ1OT1, and 0 with hypermethylation at H19. Of the 8 patients with UPD, 4 had tumors (3 hepatoblastomas, 1 Wilms tumor); 0/3 patients with hypomethylation at KCNQ1OT1 had a tumor; of the remaining 40 with no molecular alterations, 6 had tumors (3 Wilms tumors, 2 neuroblastomas, 1 adrenocortical adenoma).

The cystic fibrosis transmembrane conductance regulator gene and ion channel function in patients with idiopathic pancreatitis.

Cystic fibrosis transmembrane conductance regulator (CFTR) gene mutations are associated with cystic fibrosis (CF)-related monosymptomatic conditions, including idiopathic pancreatitis. We evaluated prospectively enrolled patients who had idiopathic recurrent acute pancreatitis or idiopathic chronic pancreatitis, healthy controls, CF heterozygotes, and CF patients (pancreatic insufficient or sufficient) for evidence of CFTR gene mutations and abnormalities of ion transport by sweat chloride and nasal potential difference testing. DNA samples from anonymous blood donors were controls for genotyping.

Providing information at the point of care: educational diagnostic reports from a genetic testing service provider.

Strategies to facilitate the provisioning of genetic health-care services by primary care physicians will improve access to these services for the average patient while making the most efficient use of limited human and financial resources within the health-care system. Genetic laboratories have become a major source of information and consultation for clinicians ordering genetic tests. This article describes the development and evaluation of a program to provide physician-directed information from a molecular testing facility to assist physicians in selecting and counseling patients and interpreting genetic test results.

Prenatal diagnosis of Apert syndrome: report of two cases.

Two de novo cases with Apert Syndrome detected prenatally are presented herein. In the first, fetal ultrasound findings of syndactyly of the hands, craniosynostosis and proptosis resulted in a prenatal diagnosis in the nineteenth week of gestation. This is the earliest prenatal diagnosis of this syndrome in a not-at-risk case.

Screening of patients with craniosynostosis: molecular strategy.

Craniosynostosis is the premature fusion of calvarial bones leading to an abnormal head shape. The craniosynostosis syndromes are clinically heterogeneous with overlapping features, which make an accurate diagnosis difficult at times. Although the clarification of a genetic lesion does not have a direct impact on patient management in many cases, there is a significant benefit in providing accurate prenatal diagnosis.

Renal abnormalities in beckwith-wiedemann syndrome are associated with 11p15.5 uniparental disomy.

Beckwith-Wiedemann syndrome (BWS) is a somatic overgrowth syndrome characterized by a variable incidence of congenital anomalies, including hemihyperplasia and renal malformations. BWS is associated with disruption of genomic imprinting and/or mutations in one or more genes encoded on 11p15.5, including CDKN1C (p57(KIP2)).