Wolf-Hirschhorn Syndrome Research Articles

Feasibility and Reliability of Functional Mobility Measures in Children With Cri du Chat (5P-) Syndrome.

To investigate feasibility and reliability of functional mobility measures in children with Cri du Chat syndrome (CdCS). Nine children with CdCS and 9 children with typical development (TD) completed the Timed Up and Go, 5 times sit-to-stand test, Timed Floor to Stand, and 4 Square Step Test. Feasibility was determined using testing time and need for modifications. Intraclass correlation coefficients were calculated for intrarater and interrater reliability. Children with CdCS required modifications to complete all tests. One child with CdCS completed the 4 Square Step Test. Good reliability was found for both groups. The Timed Up and Go, 5 times sit-to-stand test, and Timed Floor to Stand are feasible and reliable tools for children with TD between ages of 5 and 15 years; however, may require modifications to the protocols to be feasible in children with CdCS. The 4 Square Step Test is not a feasible tool for children with CdCS.

Commentary on "Feasibility and Reliability of Functional Mobility Measures in Children With Cri du Chat (5P-) Syndrome".

Commentary on "Feasibility and Reliability of Functional Mobility Measures in Children With Cri du Chat (5P-) Syndrome".

A new 1p36.13-1p36.12 microdeletion syndrome characterized by learning disability, behavioral abnormalities, and ptosis.

Two 1p36 contiguous gene deletion syndromes are known so far: the terminal 1p36 deletion syndrome and a 1p36 deletion syndrome with a critical region located more proximal at 1p36.23-1p36.22. We present even more proximally located overlapping deletions from seven individuals, with the smallest region of overlap comprising 1 Mb at 1p36.13-1p36.12 (chr1:19077793-20081292 (GRCh37/hg19)) defining a new contiguous gene deletion syndrome. The characteristic features of this new syndrome are learning disability or mild intellectual disability, speech delay, behavioral abnormalities, and ptosis. The genes UBR4 and CAPZB are considered the most likely candidate genes for the features of this new syndrome.

Клиническая и молекулярно-цитогенетическая характеристика двух случаев инвертированной дупликации со смежной терминальной делецией 8р

Синдром инвертированной дупликации короткого плеча хромосомы 8 со смежной терминальной делециенй (inv dup del(8p), ORPHA 96092) - редкая хромосомная аномалия (ХА) с частотой 1/10000-1/30000 живорожденных. В статье представлены клинические и молекулярно-цитогенетические характеристики двух неродственных пациентов с синдромом inv dup del(8p) и уточнены механизмы формирования хромосомного дисбаланса. Inverted duplication deletion 8p syndrome (inv dup del(8p), ORPHA 96092) is a rare chromosomal abnormality with a frequency of 1:10,000 - 30,000 newborns. Clinical manifestations of this syndrome include mental retardation, facial anomalies, hypoplasia/agenesis of corpus callosum, scoliosis and/or kyphosis, hypotonia, congenital heart defects. The article presents the clinical and molecular cytogenetic characteristics of two patients with inv dup del (8p) syndrome and clarifies the formation mechanisms.

Cardiac-specific inactivation of Prdm16 effects cardiac conduction abnormalities and cardiomyopathy-associated phenotypes.

A variant in the PRDM16 locus has been correlated with QRS duration in an electrocardiogram genome-wide association study, and the deletion of PRDM16 has been implicated as a causal factor of the dilated cardiomyopathy that is linked to 1p36 deletion syndrome. We aimed to determine how a null mutation of Prdm16 affects cardiac function and study the underlying mechanism of the resulting phenotype in an appropriate mouse model. We used cardiac-specific Prdm16 conditional knockout mice to examine cardiac function by electrocardiography. QRS duration and QTc interval increased significantly in cardiac-specific Prdm16 knockout animals compared with wild-type mice. Further, we assessed cardiomyopathy-associated features by trichrome staining, densitometry, and hydroxyproline assay. Prdm16-null hearts showed greater fibrosis and cardiomyocyte hypertrophy. By quantitative real-time PCR, Prdm16-null hearts upregulated extracellular matrix-related genes (Ctgf, Timp1) and α-smooth muscle actin (Acta2), a myofibroblast marker. Moreover, TGF-β signaling was activated in Prdm16-null hearts, as evidenced by increased Tgfb1-3 transcript levels and phosphorylated Smad2. However, the inhibition of TGF-β receptor did not reverse the aberrations in conduction in cardiac-specific Prdm16 knockout mice. To determine the underlying mechanisms, we performed RNA-seq using mouse left ventricular tissue. By functional analysis, Prdm16-null hearts experienced dysregulated expression of ion channel genes, including Kcne1, Scn5a, Cacna1h, and Cacna2d2. Mice with Prdm16-null hearts develop abnormalities in cardiac conduction and cardiomyopathy-associated phenotypes, including fibrosis and cellular hypertrophy. Further, the RNA-seq findings suggest that impairments in ion homeostasis (Ca2+, K+, and Na+) may at least partially underlie the abnormal conduction in cardiac-specific Prdm16 knockout mice.NEW & NOTEWORTHY This is the first study that describes aberrant cardiac function and cardiomyopathy-associated phenotypes in an appropriate murine genetic model with cardiomyocyte-specific Prdm16-null mutation. It is noteworthy that the correlation of PRDM16 with QRS duration is replicated in a murine animal model and the potential underlying mechanism may be the impairment of ion homeostasis.

Algorithm for the diagnosis of patients with neurodevelopmental disorders and suspicion of a genetic syndrome

The wide range of chromosome aberrations seen in neurodevelopmental disorders may not always be characterized by means of a chromosome analysis. The objective of this study was to determine the genetic etiology of these disorders in patients with congenital neurological conditions and clinical suspicion of a genetic disorder using a clinical and molecular testing algorithm. Among 111 studied children, 71 showed submicroscopic chromosome aberrations associated with microdeletion/microduplication syndromes: DiGeorge (22 cases), Prader-Willi (26 cases), Angelman (2 cases), WilliamsBeuren (17 cases), Smith-Magenis (1 case), Miller-Dieker (1 case), and cri du chat syndrome (1 case). Additionally, a de novo trisomy 17p12p11.2 due to an unbalanced insertion into 5p13.1 was identified in a 3-year-old child. In most cases, the use of a clinical method together with molecular techniques, such as fluorescence in situ hybridization, has allowed to make an accurate diagnosis in patients and/or families with neurodevelopmental disorders.

Механизмы формирования инвертированной дупликации со смежной терминальной делецией короткого плеча хромосомы 8

Inverted duplication deletion 8p syndrome (inv dup del(8p)) is a rare chromosomal abnormality with a frequency of 1:10,000 – 30,000 newborns. Clinical manifestations of this syndrome include mental retardation, facial anomalies, hypoplasia/agenesis of corpus callosum, scoliosis and/or kyphosis, hypotonia, congenital heart defects. Several models are proposed to explain the formation of inverted duplications adjacent to terminal deletions in the human genome. The features of inv dup del (8p) formation mechanisms and reported data on molecular cytogenetic characteristics of chromosomal rearrangement are considering in this review.

Síndrome Cri Du Chat

El síndrome de maullido de gato o deleción 5p es una alteración en la cual hay una disminución del material genético en el brazo corto del par de cromosomas 5, es un síndrome poco frecuente con una incidencia de 1/50000 nacimientos, teniendo mayor incidencia en el sexo femenino. No siendo establecido en razas o zonas geográficas.
 Fue descrito por primera vez 1963 por el doctor francés Jerome Lejeune, mediante un análisis citogenético en cual consiste en la observación de los genes.
 El nombre Cri Du Chat es de origen francés y significa llanto o maullido de gato
 Como resultado a la falta de algunos genes encargados de establecer el lenguaje, la capacidad cognitiva y la formación de estructuras corporales, los aspectos antes mencionados suelen presentar defectos.Siendo su principal característica el llanto parecido al maullido de un gato debido a la laringomalasia acompañada de hipoplasia de epiglotis y a la relajación de los pliegues superiores ariepigloticos, esto causa que los Mz de la voz tengan una frecuencia de 600-900 Mz.

Targeted analysis reveals alteration in pathway in 5p minus individuals

Cri du Chat or 5p minus (5p-) syndrome is characterized by a deletion located on the chromosome 5 short (-p) arm and has an incidence rate of 1 in 50,000 individuals worldwide. This disease manifests in disturbances across a range of systems biochemicals. Therefore, a targeted metabolomics analysis was evaluated in patients with 5p- syndrome to help unravel the biochemical changes that occur in this disease. Urine samples were collected from people of both sexes aged 1-38 years old and analyzed by ultra-performance liquid chromatography coupled to mass spectrometry. Student' statistical test, metabolomic pathway analysis and metabolite set enrichment analysis were applied to the data. Alterations of some amino acids and amine biogenics levels were found in Cri du Chat Syndrome individuals. The alteration of most of these metabolites is associated with energy recuperation and glycolysis. In general, we found the catabolism of some metabolic pathways to be affected in 5p- patients.

Impacts of Down Syndrome and Chromosome Abnormalities on Journal

On behalf of the Board of the Journal of Down Syndrome & Chromosome Abnormalities (JDSCA) and my coeditors, I am glad to present the Volume 6, Issue 2 of the journal. Journal is maintaining areas like chromosome abnormalities, risk of Down syndrome, genetic challenges of Down syndrome, Effects of Down syndrome, Diagnosis of Down syndrome, Study of chromosome 21, diagnostic testing, screening and chromosomal abnormalities like WolfHirschhorn syndrome, Jacobsen Syndrome, Angelman syndrome, Turner syndrome, 22q11.2 deletion syndrome, Triple X Syndrome, Williams Syndrome, Cri du Chat Syndrome, Trisomy 13/Patau syndrome, Trisomy 18/Edwards syndrome, Cat eye syndrome, Fragile X syndrome. Journal of Down Syndrome & Chromosome Abnormalities (JDSCA) has released 6 volumes successfully and more than 5 new editors were added to the Editorial Board. Journal quality and citations are improved and published more than 60% articles from higher income countries.

Distal interstitial 1p36 deletion syndrome in a case of global developmental delay with multiple congenital malformations

Distal interstitial 1p36 deletion syndrome in a case of global developmental delay with multiple congenital malformations

Do microdeletions lead to immune deficiency?

IntroductionMicrodeletion syndromes may be accompanied by immunological disorders. This study aimed to evaluate the clinical and laboratory data as well as the immune functions of patients diagnosed with a microdeletion syndrome.Material and methods39 patients diagnosed with microdeletion syndrome who were monitored at the Pediatric Genetics and Immunology clinics at Dr. Behcet Uz Children’s Hospital were included in this study. All data for this research were obtained from patient records and by individual consultation with their parents.ResultsOf the 39 patients, 15 were monitored for a diagnosis of Williams syndrome, 12 for DiGeorge syndrome, 4 for Prader-Willi syndrome, 2 for Wolf-Hirschhorn syndrome, 1 for a 1p36 deletion, 1 for Smith-Magenis syndrome, 2 for Trichorhinophalangeal syndrome type 2 (TRPS2), and 2 for Cri-du-chat syndrome. Of these 39 patients, 10 (25.6%) had a medical history of frequent upper respiratory tract infections. One of the cases with TRPS2 and another with Smith-Magenis syndrome had previously received intravenous antibiotic therapy for infectious disease. Five of the 12 patients with DiGeorge syndrome had low T lymphocytes. Two of the patients with DiGeorge syndrome with a history of frequent infections, with hypogammaglobinemia, and low lymphocytes were receiving regular intravenous immunoglobulin (IVIG) replacement.ConclusionsIt must be taken into account that patients with microdeletion syndromes, especially those with DiGeorge syndrome, may also have immunodeficiencies; therefore, these patients should be closely monitored to prevent development of any complications.

Trisomy 12p Syndrome Presenting with Fetal Growth Restriction and Polyhydramnios

A 39-year-old nulliparous woman was referred at 36+6 weeks gestational age, and a prenatal fetal ultrasonography examination found fetal growth restriction (2,190 g <5%), polyhydramnios (amniotic fluid index: 31.76 cm), and absent end-diastolic flow in the umbilical artery. A male baby was born, and fetal dysmorphism including round face, long philtrum, low-set ears, chest retraction, edematous hands and feet, and a simian line on both hands were identified. He was diagnosed with trisomy 12p [der(18)t(12;18)(p11.2;p11.31)] by chromosomal study. The father’s chromosomes appeared normal; however, the mother’s chromosomes had a balanced translocation identified as t(12;18)(p11.2;p11.31). Patent ductus arteriosus, germinal matrix hemorrhage, and hemivertebrae were diagnosed, and respiratory distress, hyperinsulinemic hypoglycemia, and hypothyroidism were also detected. The combination of fetal growth restriction and polyhydramnios may be a significant sign of chromosomal abnormalities, and targeted sonography and a chromosomal analysis should be offered prenatally in such cases.

Rapid prenatal aneuploidy detection of BACs-on-Beads assay in 4961 cases of amniotic fluid samples

Objective To evaluate the diagnostic value of the BACs-on-Beads (BoBs) assay for the rapid diagnosis of common aneuploidies and microdeletions. Methods A total of 4961 pregnant women admitted to the Wuxi Maternity and Child Health Care Hospital Affiliated to Nanjing Medical University from January 2017 to March 2019 were enrolled. BoBs assay and conventional karyotyping were applied to detect amniotic fluid samples with various indications for prenatal diagnosis. Chromosomal microarray analysis (CMA) and maternal cell contamination (MCC) tests were used for further validation. Results The overall abnormality detection rates (BoBs associated with karyotyping) were 4.25% (211/4961). The prenatal diagnosis success rate of karyotyping was 99.4% (4933/4961), compared to 100% (4961/4961) using the BoBs assays. The BoBs assay was similar to karyotyping for the detection of trisomy 21 (1.01%, 50/4961), trisomy 18 (0.40%, 20/4961), trisomy 13 (0.04%, 2/4961), and sex chromosomal aneuploidies (0.15%, 12/4961). The BoBs assay also identified sex chromosomal microduplications/microdeletions (1.73%, 86/4961), 22q11.2 microdeletions/microduplications (0.1%, 5/4961), and Cri du Chat syndrome (0.02%, 1/4961) which were missed by karyotyping. The sensitivity for the detection of numerical chromosomal abnormalities of the BoBs assay and karyotyping analysis was 100% (95/95, 95% CI: 1.0–1.0) and 98.9% (94/95, 95% CI: 0.969–1.010), respectively. The sensitivity of detecting structural chromosomal abnormalities in the BoBs assay was significantly higher than those of karyotyping (79.3%, 92/116, 95% CI: 0.718–0.868) versus 21.6% (25/116, 95% CI: 0.140–0.291) (p < .01). Conclusions The BoBs assay is a reliable and rapid test for the detection of common aneuploidies and nine microdeletion syndromes with high sensitivity and accuracy in prenatal diagnosis. The assay can compensate for the limitations of karyotyping analysis.

50 Years Ago in TheJournal ofPediatrics: Human Chromosomal Deletion: Two Patients with the 4p–Syndrome

50 Years Ago in TheJournal ofPediatrics: Human Chromosomal Deletion: Two Patients with the 4p–Syndrome

Melatonin reverses the oxidative stress and mitochondrial dysfunction caused by LETM1 silencing.

LETM1 is a mitochondrial inner-membrane protein, which is encoded by a gene present in a locus of 4p, which, in turn, is deleted in the Wolf-Hirschhorn Syndrome, and is assumed to be related to its pathogenesis. The cellular damage caused by the deletion is presumably related to oxidative stress. Melatonin has many beneficial roles in protecting mitochondria by scavenging reactive oxygen species, maintaining membrane potential, and improving functions. The aim of this study was to investigate the effects of melatonin administration to LETM1-silenced mouse embryonic fibroblast cells as a cellular model for LETM1 deficiency. We transfected mouse embryonic fibroblast cells with a pair of siRNA against LETM1 and monitored the oxidative stress and mitochondrial functions with or without melatonin addition. MnSOD expression and aconitase activity decreased and oxidized protein levels increased in LETM1-silenced cells. LETM1 suppression did not alter the expression of OXPHOS complexes, but the oxygen consumption rates decreased significantly; however, this change was not related to complex I but instead involved complex IV and complex II. Melatonin supplementation effectively normalized the parameters studied, including the oxygen consumption rate. Our findings identified a novel effect of LETM1 deficiency on cellular respiration via complex II as well as a potential beneficial role of melatonin treatment. On the other hand, these effects may be specific to the cell line used and need to be verified in other cell lines.

A case of prenatal diagnosis of 18p deletion syndrome following noninvasive prenatal testing

BackgroundChromosome 18p deletion syndrome is a disease caused by the complete or partial deletion of the short arm of chromosome 18, there were few cases reported about the prenatal diagnosis of 18p deletion syndrome. Noninvasive prenatal testing (NIPT) is widely used in the screening of common fetal chromosome aneuploidy. However, the segmental deletions and duplications should also be concerned. Except that some cases had increased nuchal translucency or holoprosencephaly, most of the fetal phenotype of 18p deletion syndrome may not be evident during the pregnancy, 18p deletion syndrome was always accidentally discovered during the prenatal examination.Case presentationsIn our case, we found a pure partial monosomy 18p deletion during the confirmation of the result of NIPT by copy number variation sequencing (CNV-Seq). The result of NIPT suggested that there was a partial or complete deletion of X chromosome. The amniotic fluid karyotype was normal, but result of CNV-Seq indicated a 7.56 Mb deletion on the short arm of chromosome 18 but not in the couple, which means the deletion was de novo deletion. Finally, the parents chose to terminate the pregnancy.ConclusionsTo our knowledge, this is the first case of prenatal diagnosis of 18p deletion syndrome following NIPT.NIPT combined with ultrasound may be a relatively efficient method to screen chromosome microdeletions especially for the 18p deletion syndrome.

Diagnostic and clinical utility of whole genome sequencing in a cohort of undiagnosed Chinese families with rare diseases

Rare diseases are usually chronically debilitating or even life-threatening with diagnostic and therapeutic challenges in current clinical practice. It has been estimated that 80% of rare diseases are genetic in origin, and thus genome sequencing-based diagnosis offers a promising alternative for rare-disease management. In this study, 79 individuals from 16 independent families were performed for whole-genome sequencing (WGS) in an effort to identify the causative mutations for 16 distinct rare diseases that are largely clinically intractable. Comprehensive analysis of variations, including simple nucleotide variants (SNVs), copy-number variations (CNVs), and structural variations (SVs), was implemented using the WGS data. A flexible analysis pipeline that allowed a certain degree of misclassification of disease status was developed to facilitate the identification of causative variants. As a result, disease-causing variants were identified in 10 of the 16 investigated diseases, yielding a diagnostic rate of 62.5%. Additionally, new potentially pathogenic variants were discovered for two disorders, including IGF2/INS-IGF2 in mitochondrial disease and FBN3 in Klippel–Trenaunay–Weber syndrome. Our WGS analysis not only detected a CNV associated with 3p deletion syndrome but also captured a simple sequence repeat (SSR) variation associated with Machado–Joseph disease. To our knowledge, this is the first time the clinical WGS analysis of short-read sequences has been used successfully to identify a causative SSR variation that perfectly segregates with a repeat expansion disorder. After the WGS analysis, we confirmed the initial diagnosis for three of 10 established disorders and modified or corrected the initial diagnosis for the remaining seven disorders. In summary, clinical WGS is a powerful tool for the diagnosis of rare diseases, and its diagnostic clarity at molecular levels offers important benefits for the participating families.

International meeting on Wolf-Hirschhorn syndrome: Update on the nosology and new insights on the pathogenic mechanisms for seizures and growth delay.

"An International Meeting on Wolf-Hirschhorn Syndrome (WHS)" was held at The University Hospital La Paz in Madrid, Spain (October 13-14, 2017). One hundred and twenty-five people, including physicians, scientists and affected families, attended the meeting. Parent and patient advocates from the Spanish Association of WHS opened the meeting with a panel discussion to set the stage regarding their hopes and expectations for therapeutic advances. In keeping with the theme on therapeutic development, the sessions followed a progression from description of the phenotype and definition of therapeutic endpoints, to definition of genomic changes. These proceedings will review the major points of discussion.

The case of rare genetic mutation in a child with the Wolf–Hirschhorn syndrome from the family irradiated during the Chernobyl accident

Wolf – Hirschhorn syndrome is a rare genetic disease caused by the deletion of the end of the short arm of the 4th chromosome; it is manifested by numerous congenital malformations, delayed physical and psychomotor development. The article describes clinical experience of managing a patient with Wolff – Hirschhorn syndrome born to exposed parents who lived in a territory contaminated with radionuclides after the Chernobyl accident. The article describes pathogenetic aspects of the development of the disease and the need for timely diagnostics.