Co-occurrence of severe Goltz-Gorlin syndrome and pentalogy of Cantrell - Case report and review of the literature

Goltz Syndrome Combined with Triple X Syndrome, a Case Report

Goltz syndrome is a rare X-linked dominant multisystem disorder that presents with ectoderm and mesoderm-derived symptoms. Skin manifestations including congenital patchy skin aplasia, congenital nodular fat herniation, congenital hypo- or hyperpigmentation along Blaschko's lines, telangiectasia, and congenital ridged dysplastic nails are typical in this disorder. Almost all cases of Goltz syndrome correspond to female newborns and that hemizygosis makes the syndrome fetal in males. Triple X syndrome is a relatively common congenital disorder that presents with mild to no symptoms in the developmental and psychiatric realm. The patient reported here was born with multisystem anomaly affecting the eyes, craniofacial region, cardiovascular system, skin, and limbs. A G-banding chromosomal study revealed 47, XXX. She was diagnosed with Goltz syndrome owing to her distinctive skin manifestations. The congenital cervical skin defect healed with conservative treatment. The facial cleft, cleft lip-palate, and syndactyly were successfully treated with multiple surgical treatments. The combination of triple X syndrome and Goltz syndrome is very rare. We describe the expression of presenting with both syndromes simultaneously.

Pentalogy of Cantrell in Two Neonate Littermate Puppies: A Spontaneous Animal Model Suggesting Familial Inheritance

Developmental anomalies are an important cause of stillbirth and early perinatal death in companion animals. Many of these disorders remain poorly understood and provide an opportunity as a spontaneous animal model for human disease. Pentalogy of Cantrell is a rare congenital syndrome described in human neonates. It is a ventral midline closure defect with a proposed familial inheritance in humans. This syndrome involves five defects, including the thoracoabdominal wall, sternal, diaphragmatic, pericardial and cardiac malformations. Diverse expressions of these defects have been described in humans and sporadically in domestic animals. This severe syndrome commonly harbors a poor prognosis, posing an ethical and surgical dilemma. To better understand this syndrome and its presentation in dogs, we describe two rare cases of Pentalogy of Cantrell in a litter of papillon dogs. The affected puppies had anomalies compatible with the Pentalogy of Cantrell, including thoracoabdominal schisis, ectopia cordis, sternal cleft, pericardial agenesis, and diaphragmatic defects. The diagnosis was confirmed by advanced imaging (computed tomography) and postmortem examinations. The family history of this litter was explored and other cases in domestic animals were reviewed. This is the first report of the complete Pentalogy of Cantrell with ectopia cordis in the dog and the only report on papillons. Similar to human cases, possible familial inheritance and suspected male gender bias were observed. Further research on this novel animal model, its pathogenesis and its hereditary basis, may be helpful in better understanding this rare developmental disorder.

Evaluation of clinical features and outcome of eight fetuses with ectopia cordis; A study from a fetal cardiology center

We aim to evaluate the clinical course and outcome of cases with a prenatal diagnosis of ectopia cordis in our center. In this retrospective study, we analyzed clinical variables including gestational age at diagnosis, maternal age, associated cardiac, extracardiac, genetic anomalies and, outcome in prenatally diagnosed ectopia cordis cases in our tertiary referral center. Eight ectopia cordis cases from seven pregnancies were included in the study. All fetuses had complete type of ectopia cordis and pentalogy of Cantrell. Five multiple pregnancies were found, four were twin pregnancies (three dichorionic diamniotic, one monochorionic monoamniotic) and one was triplet (trichorionic triamniotic). In the monochorionic monoamniotic twin pregnancy, both fetuses have pentalogy of Cantrell. Two cases had intracardiac structural defects including Tetralogy of Fallot and hypoplastic right heart syndrome. Three pregnancies were terminated, four cases delivered alive could not survive beyond the neonatal period. The striking feature in our study is its association with multiple pregnancies.

Pentalogy of Cantrell With a Maxillary Gap Identified at 12 Weeks of Gestation

Pentalogy of Cantrell (POC) is a rare syndrome, with an omphalocele and ectopia cordis (EC) being pathognomonic anomalies. In this case report, a 12-week fetus, for nuchal translucency (NT) assessment, displayed a sac protruding through the midline of the fetal abdomen and lower thorax. The fetus’ cardiac activity was detected within the sac. These sonographic appearances are consistent with omphalocele and EC, respectively. A thickened NT and cystic hygroma (CH) were also identified. An important finding was a 1.8 mm maxillary gap (MG), which is a new marker for possible early diagnosis of cleft lip and palate (CLP), in the first trimester. The coexistence of a MG with POC is unique.

Underlying genetic etiologies of congenital diaphragmatic hernia

Congenital diaphragmatic hernia (CDH) is often detectable prenatally. Advances in genetic testing have made it possible to obtain a molecular diagnosis in many fetuses with CDH. Here, we review the aneuploidies, copy number variants (CNVs), and single genes that have been clearly associated with CDH. We suggest that array-based CNV analysis, with or without a chromosome analysis, is the optimal test for identifying chromosomal abnormalities and CNVs in fetuses with CDH. To identify causative sequence variants, whole exome sequencing (WES) is the most comprehensive strategy currently available. Whole genome sequencing (WGS) with CNV analysis has the potential to become the most efficient and effective means of identifying an underlying diagnosis but is not yet routinely available for prenatal diagnosis. We describe how to overcome and address the diagnostic and clinical uncertainty that may remain after genetic testing, and review how a molecular diagnosis may impact recurrence risk estimations, mortality rates, and the availability and outcomes of fetal therapy. We conclude that after the prenatal detection of CDH, patients should be counseled about the possible genetic causes of the CDH, and the genetic testing modalities available to them, in accordance with generally accepted guidelines for pretest counseling in the prenatal setting.

Novel insights into PORCN mutations, associated phenotypes and pathophysiological aspects

BACKGROUND

Goltz syndrome (GS) is a X-linked disorder defined by defects of mesodermal- and ectodermal-derived structures and caused by PORCN mutations. Features include striated skin-pigmentation, ocular and skeletal malformations and supernumerary or hypoplastic nipples. Generally, GS is associated with in utero lethality in males and most of the reported male patients show mosaicism (only three non-mosaic surviving males have been described so far). Also, precise descriptions of neurological deficits in GS are rare and less severe phenotypes might not only be caused by mosaicism but also by less pathogenic mutations suggesting the need of a molecular genetics and functional work-up of these rare variants.

RESULTS

We report two cases: one girl suffering from typical skin and skeletal abnormalities, developmental delay, microcephaly, thin corpus callosum, periventricular gliosis and drug-resistant epilepsy caused by a PORCN nonsense-mutation (c.283C > T, p.Arg95Ter). Presence of these combined neurological features indicates that CNS-vulnerability might be a guiding symptom in the diagnosis of GS patients. The other patient is a boy with a supernumerary nipple and skeletal anomalies but also, developmental delay, microcephaly, cerebral atrophy with delayed myelination and drug-resistant epilepsy as predominant features. Skin abnormalities were not observed. Genotyping revealed a novel PORCN missense-mutation (c.847G > C, p.Asp283His) absent in the Genome Aggregation Database (gnomAD) but also identified in his asymptomatic mother. Given that non-random X-chromosome inactivation was excluded in the mother, fibroblasts of the index had been analyzed for PORCN protein-abundance and -distribution, vulnerability against additional ER-stress burden as well as for protein secretion revealing changes.

CONCLUSIONS

Our combined findings may suggest incomplete penetrance for the p.Asp283His variant and provide novel insights into the molecular etiology of GS by adding impaired ER-function and altered protein secretion to the list of pathophysiological processes resulting in the clinical manifestation of GS.

Anomalous Connection of Umbilical Vessels to the Left Ventricle: Case Report

The anomalous connection of umbilical vessels to the heart is rare and has not yet been reported in the international scientific literature. Herein, we report the case of a newborn who was diagnosed with an anomalous connection of the umbilical vessels to the left ventricle. These anomalous vessels were functionally open for 2 weeks, and cellulitis was present in the area of the blood vessels connected to the skin. We performed division of these abnormal vessels and removal of the skin lesion.

The Role of De Novo Variants in Patients with Congenital Diaphragmatic Hernia

The genetic etiology of congenital diaphragmatic hernia (CDH), a common and severe birth defect, is still incompletely understood. Chromosomal aneuploidies, copy number variations (CNVs), and variants in a large panel of CDH-associated genes, both de novo and inherited, have been described. Due to impaired reproductive fitness, especially of syndromic CDH patients, and still significant mortality rates, the contribution of de novo variants to the genetic background of CDH is assumed to be high. This assumption is supported by the relatively low recurrence rate among siblings. Advantages in high-throughput genome-wide genotyping and sequencing methods have recently facilitated the detection of de novo variants in CDH. This review gives an overview of the known de novo disease-causing variants in CDH patients.

Surgical management of total sternal cleft in a pentalogy of Cantrell neonate

Sternal cleft is a rare malformation with significant morbidity and mortality. It has been associated with other midline fusion defects, most significantly Cantrell's pentalogy, involving the sternum, pericardium, heart, diaphragm, and abdominal wall. This study reported a successfully managed case of a newborn with a total sternal cleft and Cantrell's pentalogy. A review of literature and pertinent management principles was also conducted.

Management of Congenital Diaphragmatic Hernia (CDH): Role of Molecular Genetics

Congenital diaphragmatic hernia (CDH) is a relatively common major life-threatening birth defect that results in significant mortality and morbidity depending primarily on lung hypoplasia, persistent pulmonary hypertension, and cardiac dysfunction. Despite its clinical relevance, CDH multifactorial etiology is still not completely understood. We reviewed current knowledge on normal diaphragm development and summarized genetic mutations and related pathways as well as cellular mechanisms involved in CDH. Our literature analysis showed that the discovery of harmful de novo variants in the fetus could constitute an important tool for the medical team during pregnancy, counselling, and childbirth. A better insight into the mechanisms regulating diaphragm development and genetic causes leading to CDH appeared essential to the development of new therapeutic strategies and evidence-based genetic counselling to parents. Integrated sequencing, development, and bioinformatics strategies could direct future functional studies on CDH; could be applied to cohorts and consortia for CDH and other birth defects; and could pave the way for potential therapies by providing molecular targets for drug discovery.

Twin pregnancy in which both fetuses have Cantrell's pentalogy: A case report and literature review

Cantrell's pentalogy is a congenital multiple malformation consisting of midline supraumbilical thoraco-abdominal wall defects, anterior and pericardial diaphragm defects, lower sternum defects, ectopia cordis and various intracardiac anomalies. Complete pentalogy is very rare. Some additional anomalies may accompany pentalogy and there are cases in the literature where chromosomal anomalies and pentalogy are seen. Cases of Cantrell's pentalogy in twin pregnancies are rare. Twin pregnancies with Cantrell's pentalogy in both fetuses are one of the rarest cases in the literature. In this study, we presented a twin pregnancy case with Cantrell's pentalogy in both fetuses and we reviewed twin pregnancy cases in which Cantrell's pentalogy was seen in the literature. In our case, anomalies were found in both fetuses in the evaluation performed on a 32-year-old, gravida 2, para 1 woman with 10 weeks + 5 days monochorionic-monoamniotic twin pregnancy. The first fetus had ectopia cordis, cystic hygroma and increased nuchal thickness (4.6 mm), and the anterior abdominal wall was in contact with the amniotic band. The second fetus had ectopia cordis omphalocele, cystic hygroma, holoprosencephaly and a single lower extremity deficiency. Both fetuses were pre-diagnosed with Cantrell's pentalogy and the parents were informed about the adverse course of the fetuses. After the completion of the legal procedures, with the approval and decision of the parents, termination was made in the 11th week of pregnancy. External images of the fetuses confirmed the diagnosis. The family denied the autopsy procedure. When we review the literature, twin pregnancies complicated by Cantrell's pentalogy are divided into 3 groups: Group1- cases where one of the twins has completely normal phenotype and the other twin has Cantrell's pentalogy; Group2- cases where one of the twins has Cantrell's pentalogy and the other twin does not have the Cantrell's pentalogy but has several anomalies; Group3- cases where both fetuses have Cantrell's pentalogy. In conclusion, early diagnosis of twin pregnancy cases complicated by Cantrell's pentalogy and determination of all anomalies in both fetuses are very important in terms of obstetric management.

The influence of genetics in congenital diaphragmatic hernia

Congenital diaphragmatic hernia (CDH) is a common birth defect that is associated with significant morbidity and mortality, especially when associated with additional congenital anomalies. Both environmental and genetic factors are thought to contribute to CDH. The genetic contributions to CDH are highly heterogeneous and incompletely defined. No one genetic cause accounts for more than 1-2% of CDH cases. In this review, we summarize the known genetic causes of CDH from chromosomal anomalies to individual genes. Both de novo and inherited variants contribute to CDH. Genes causing CDH are increasingly identified from animal models and from genomic strategies including exome and genome sequencing in humans. CDH genes are often transcription factors, genes involved in cell migration or the components of extracellular matrix. We provide clinical genetic testing strategies in the clinical evaluation that can identify a genetic cause in up to ∼30% of patients with non-isolated CDH and can be useful to refine prognosis, identify associated medical and neurodevelopmental issues to address, and inform family planning options.

Complete and Incomplete Pentalogy of Cantrell

Pentalogy of Cantrell (PC) is a malformation characterized by defects in the ventral abdominal wall, lower sternum, diaphragmatic pericardium, anterior diaphragm associated with omphalocele, thoraco-abdominal ectopia cordis, diaphragmatic hernia, and intracardiac abnormalities. PC is stratified as complete or incomplete and we present both the complete and incomplete forms.

Pentalogy of Cantrell

Pentalogy of Cantrell is a constellation of five congenital defects that pose a unique challenge for surgeons. Defects of the heart, pericardium, diaphragm, sternum, and anterior abdominal wall are pathognomonic. Although the incidence is low, it is critical to identify it in a timely fashion in order to adequately address all aspects. Early diagnosis, supportive care, and strategic surgical planning with a multidisciplinary team are all key components in managing patients with Pentalogy of Cantrell. In this text we sought to explore the evolution of both the understanding and treatment for this complex entity and provide current recommendations to today's pediatric caregivers.

Goltz syndrome in males: A clinical report of a male patient carrying a novel PORCN variant and a review of the literature

Here, we report a novel mosaic mutation in the PORCN gene in a male Goltz syndrome patient. We also compare the phenotypes of all reported males with a confirmed molecular diagnosis. This report serves to further clarify the phenotype of Goltz syndrome and suggests that expression in males varies.

Abrogation of TGF-beta signalling in TAGLN expressing cells recapitulates Pentalogy of Cantrell in the mouse

Pentalogy of Cantrell (PC) is a rare multi-organ congenital anomaly that impedes ventral body wall closure and results in diaphragmatic hernia, intra- and pericardial defects. The underlying cellular and molecular changes that lead to these severe developmental defects have remained unknown largely due to the lack of representative animal models. Here we provide in depth characterization of a mouse model with conditional ablation of TGFβRII in Transgelin (Tagln) expressing cells. We show that Tagln is transiently expressed in a variety of cells that participate in the embryonic development and patterning of ventral structures. Genetic ablation of TGFβRII in these cells leads to ventral midline closure defect, diaphragmatic hernia, dilated cardiac outflow tract and aberrant cardiac septation, providing a reliable model to study the morphological changes leading to PC. We show that myogenisis in the diaphragm is independent of TGFβ and the diaphragmatic hernia arises from fibroblast-specific migration defect. In the dorsal body wall Tagln expression is initiated after the closure process, revealing a remarkable difference between ventral and dorsal body walls development. Our study demonstrates the use of micro-CT scanning to obtain a 3-dimensional high-resolution overview of embryonic anomalies and provides the first mechanistic insight into the development of PC.

Cantrell Syndrome-A Rare Complex Congenital Anomaly: A Case Report and Literature Review

Cantrell syndrome (CS) or pentalogy of Cantrell is defined as a rare condition involving a midline anterior abdominal wall defect, a distal sternal cleft, a defect of the anterior diaphragm, and a defect of the apical pericardium with pericardio-peritoneal communication, as well as intracardiac anomalies. We report the case of a male newborn with type 2 CS diagnosed during intrauterine life based on ultrasonographic evaluation. Clinical examination at birth revealed an abdominal wall defect with extrathoracic displacement of the heart and a diastasis of the sagittal suture. Postnatal echocardiography revealed tricuspid atresia, partial extrathoracic and extra-abdominal displacement of the heart and liver, a large ventricular septal defect, severe subpulmonary stenosis, hypoplasia of the pulmonary artery, and a large hourglass-shaped left ventricle secondary to narrowing of the heart at the level of its extrathoracic displacement. Computed tomography showed additional abnormalities including increased left ventricular volume with extrathoracic apical aneurysmal dilatation below the xiphoid process at the level of anterior abdominal wall, a hypoplastic right ventricle, partial transparietal herniation of the left hepatic lobe adjacent to a left ventricular diverticulum, and an adrenal hematoma. The newborn received intensive medical management during his first week of life; however, surgical management had to be postponed owing to his unstable condition. Eventually, it was performed on the 14th day of life, but unfortunately, the newborn died shortly after the procedure.

Congenital diaphragmatic hernias: from genes to mechanisms to therapies

Congenital diaphragmatic hernias (CDHs) and structural anomalies of the diaphragm are a common class of congenital birth defects that are associated with significant morbidity and mortality due to associated pulmonary hypoplasia, pulmonary hypertension and heart failure. In ∼30% of CDH patients, genomic analyses have identified a range of genetic defects, including chromosomal anomalies, copy number variants and sequence variants. The affected genes identified in CDH patients include transcription factors, such as GATA4, ZFPM2, NR2F2 and WT1, and signaling pathway components, including members of the retinoic acid pathway. Mutations in these genes affect diaphragm development and can have pleiotropic effects on pulmonary and cardiac development. New therapies, including fetal endoscopic tracheal occlusion and prenatal transplacental fetal treatments, aim to normalize lung development and pulmonary vascular tone to prevent and treat lung hypoplasia and pulmonary hypertension, respectively. Studies of the association between particular genetic mutations and clinical outcomes should allow us to better understand the origin of this birth defect and to improve our ability to predict and identify patients most likely to benefit from specialized treatment strategies.

An Unexpected Airway Complication in a Male Patient with Goltz Syndrome

Goltz syndrome, also known as focal dermal hypoplasia, is a rare X-linked dominant multisystem syndrome presenting with cutaneous, skeletal, dental ocular, central nervous system and soft tissue abnormalities. This case report discusses an adult male patient with Goltz syndrome that was noted to have large, papillomatous, hypopharyngeal lesions upon induction of general anesthesia. We highlight challenges with airway management intraoperatively and postoperatively in patients with Goltz syndrome. Our aim is to increase awareness of the potential airway complications associated with this genetic disorder and to provide suggestions for optimal perioperative management for patients afflicted with Goltz syndrome.

Prenatal diagnosis of focal dermal hypoplasia: Report of three fetuses and review of the literature

Focal dermal hypoplasia (FDH) is a rare syndrome characterized by pleiotropic features knowing to involve mostly skin and limbs. Although FDH has been described in children and adults, the cardinal signs of the fetal phenotype are not straightforward impacting the quality of the prenatal diagnosis. We describe in depth the ultrasound, radiological, macroscopical, and histological phenotype of three female fetuses with a severe form of FDH, propose a review of the literature and an attempt to delineate minimal and cardinal signs for FDH diagnosis. This report confirms the variability of FDH phenotype, highlights unreported FDH features, and allows delineating evocative clinical associations for prenatal diagnosis, namely intrauterine growth retardation, limbs malformations, anterior wall/diaphragm defects, and eye anomalies. © 2016 Wiley Periodicals, Inc.

Growth, nutritional, and gastrointestinal aspects of focal dermal hypoplasia (Goltz-Gorlin syndrome)

Focal dermal hypoplasia (FDH) is a rare genetic disorder caused by mutations in the PORCN gene located on the X-chromosome. In the present study, we characterized the pattern of growth, body composition, and the nutritional and gastrointestinal aspects of children and adults (n = 19) affected with this disorder using clinical anthropometry and a survey questionnaire. The mean birth length (P < 0.06) and weight (P < 0.001) z-scores of the participants were lower than the reference population. The mean head circumference (P < 0.001), height (length) (P < 0.001), weight (P < 0.01), and BMI (P < 0.05) for age z-scores of the participants were lower than the reference population. The height-for-age and weight-for-age z-scores of the participants did not differ significantly between birth and current measurements. Three-fourths of the group reported having one or more nutritional or gastrointestinal problems including short stature (65%), underweight (77%), oral motor dysfunction (41%), gastroesophageal reflux (24%), gastroparesis (35%), and constipation (35%). These observations provide novel clinical information about growth, body composition, and nutritional and gastrointestinal aspects of children and adults with FDH and underscore the importance of careful observation and early clinical intervention in the care of individuals affected with this disorder.

Pentalogy of Cantrell: Case Report With Review of the Literature

BACKGROUND

Pentalogy of Cantrell is a rare, congenital disorder characterized by lower sternal defects, diaphragmatic defect, pericardial defect, supraumbilical abdominal wall abnormalities, and/or intracardiac defects. The collective defects result from failure of either differentiation or migration of mesenchymal or mesodermal structures during the embryonic phase of development. Mortality of the disease complex is high, and treatment, when appropriate, revolves around surgical correction of the associated defects.

PURPOSE

This article presents a case of pentalogy of Cantrell and examines the literature to report the most current evidence relative to the embryology and pathophysiology. In addition, the methods of pre- and postnatal diagnosis, management, and prognostic indicators are examined.

METHODS/SEARCH STRATEGY

Case report was gathered from the medical records and is provided as it occurred. The literature was searched for evidence of best management strategies as well as care implications for families.

FINDINGS/RESULTS

A female newborn was delivered at (Equation is included in full-text article.)weeks' gestation secondary to premature onset of labor. Prenatal ultrasonography identified an abdominal wall defect, diaphragmatic hernia, sternal defect, ventricular septal defect, and open neural tube defect. Examination immediately after delivery confirmed prenatal findings and a diagnosis of pentalogy of Cantrell was assigned.

IMPLICATIONS FOR PRACTICE

Patients with the diagnosis of pentalogy of Cantrell should receive antenatal counseling relative to mortality and morbidity risks. An interprofessional approach in the immediate timeframe after delivery facilitates timely diagnostics and offers families prompt confirmation of antenatal findings.

IMPLICATIONS FOR RESEARCH

Future research can focus on further elucidating genetic etiologies of pentalogy of Cantrell.

Class II pentalogy of Cantrell

Background

Pentalogy of Cantrell is a rare syndrome, first described by Cantrell and co-workers in 1958. The syndrome is characterized by the presence of five major congenital defects involving the diaphragm, abdominal wall, the diaphragmatic pericardium, lower sternum and various congenital intra-cardiac abnormalities. The syndrome has never been reported in Tanzania, although may have been reported from other African countries. Survival rate of the complete form of pentalogy of Cantrell is as low as 20%, but recent studies have reported normal growth achieved by 6 years of age where corrective surgeries were done; showing that surgical repair early in life is essential for survival.

Case presentation

The African baby residing in Tanzania was referred from a district hospital on the second day of life. She was noted to have a huge omphalocele and ectopia cordis covered by a thin membrane, with bowels visible through the membrane and the cardiac impulse visible just below the epigastrium. Despite the physical anomaly, she appeared to saturate well in room air and had stable vitals. Her chest X-ray revealed the absence of the lower segments of the sternum and echocardiography showed multiple intra-cardiac defects. Based on these findings, the diagnosis of pentalogy of Cantrell was reached. On her fifth day of life, the neonate was noted to have signs of cardiac failure characterized by easy fatigability and restlessness during feeding. Cardiac failure treatment was initiated and she was discharged on parents’ request on the second week of life. Due to inadequate facilities to undertake this complex corrective surgery, arrangements were being made to refer her abroad. In the meantime, her growth and development was satisfactory until the age of 9 months, when she ran out of the medications and succumbed to death. Her parents could no longer afford transport cost to attend the monthly clinic visits, where the infant was getting free medication refill.

Conclusions

The case reported here highlights that in resource limited settings; poor outcome in infants with complex congenital anomalies is a function of multiple factors. However, we believe that surgery would have averted mortality in this 9-month-old female infant. We hope to be able to manage these cases better in future following the recent establishment of cardiac surgery facilities at Muhimbili National Hospital.

Cardiac malposition (ectopia cordis) in a cat

OBJECTIVE

To describe a case of cardiac malposition in a cat, and the successful management of the anomaly.

CASE DESCRIPTION

A 2-year-old male neutered male British Shorthair cat weighing 7.58 kg was referred for bicavitary effusion. Ultrasonography and echocardiography demonstrated displacement of the heart into the abdomen through a diaphragmatic defect. Clinical signs of right-sided congestive heart failure were attributed to mechanical restriction of diastolic function by a constrictive segment of fibrous pericardium and to impaired venous return due to a kink in the caudal vena cava. Surgical repositioning of the heart into the thoracic cavity and a subtotal pericardectomy were performed, and the diaphragmatic defect was repaired. The patient recovered well postoperatively.

NEW OR UNIQUE INFORMATION PROVIDED

The diagnosis and management of cardiac malposition has not been previously described in cats. With timely diagnosis and surgical intervention, a favorable outcome is possible.

Limb body wall complex, amniotic band sequence, or new syndrome caused by mutation in IQ Motif containing K (IQCK)?

Limb body wall complex (LBWC) and amniotic band sequence (ABS) are multiple congenital anomaly conditions with craniofacial, limb, and ventral wall defects. LBWC and ABS are considered separate entities by some, and a continuum of severity of the same condition by others. The etiology of LBWC/ABS remains unknown and multiple hypotheses have been proposed. One individual with features of LBWC and his unaffected parents were whole exome sequenced and Sanger sequenced as confirmation of the mutation. Functional studies were conducted using morpholino knockdown studies followed by human mRNA rescue experiments. Using whole exome sequencing, a de novo heterozygous mutation was found in the gene IQCK: c.667C>G; p.Q223E and confirmed by Sanger sequencing in an individual with LBWC. Morpholino knockdown of iqck mRNA in the zebrafish showed ventral defects including failure of ventral fin to develop and cardiac edema. Human wild-type IQCK mRNA rescued the zebrafish phenotype, whereas human p.Q223E IQCK mRNA did not, but worsened the phenotype of the morpholino knockdown zebrafish. This study supports a genetic etiology for LBWC/ABS, or potentially a new syndrome.

Mesenchymal Wnt signaling promotes formation of sternum and thoracic body wall

Midline defects account for approximately 5% of congenital abnormalities observed at birth. However, the molecular mechanisms underlying the formation of the ventral body wall are not well understood. Recent studies linked mutations in Porcupine-an O-acetyl transferase mediating Wnt ligand acylation-with defects in the thoracic body wall. We hypothesized that anomalous Wnt signaling is involved in the pathogenesis of defective closure of the thoracic body wall. We generated a mouse model wherein Wntless (Wls), which encodes a cargo receptor mediating secretion of Wnt ligands, was conditionally deleted from the developing mesenchyme using Dermo1Cre mice. Wls(f/f);Dermo1(Cre/+) embryos died during mid-gestation. At E13.5, skeletal defects were observed in the forelimbs, jaw, and rib cage. At E14.5, midline defects in the thoracic body wall began to emerge: the sternum failed to fuse and the heart protruded through the body wall at the midline (ectopia cordis). To determine the molecular mechanism underlying the phenotype observed in Wls(f/f);Dermo1(Cre/+) embryos, we tested whether Wnt/β-catenin signaling was operative in developing the embryonic ventral body wall using Axin2(LacZ) and BatGal reporter mice. While Wnt/β-catenin signaling activity was observed at the midline of the ventral body wall before sternal fusion, this pattern of activity was altered and scattered throughout the body wall after mesenchymal deletion of Wls. Mesenchymal cell migration was disrupted in Wls(f/f);Dermo1(Cre/+) thoracic body wall partially due to anomalous β-catenin independent Wnt signaling as determined by in vitro assays. Deletion of Lrp5 and Lrp6 receptors, which mediate Wnt/β-catenin signaling in the mesenchyme, partially recapitulated the phenotype observed in the chest midline of Wls(f/f);Dermo1(Cre/+) embryos supporting a role for Wnt/β-catenin signaling activity in the normal formation of the ventral body wall mesenchyme. We conclude that Wls-mediated secretion of Wnt ligands from the developing ventral body wall mesenchyme plays a critical role in fusion of the sternum and closure of the secondary body wall. Thus, impaired Wls activity in the ventral body wall mesenchyme is a mechanism underlying ectopia cordis and unfused sternum.

Genetic causes of congenital diaphragmatic hernia

Congenital diaphragmatic hernia (CDH) is a moderately prevalent birth defect that, despite advances in neonatal care, is still a significant cause of infant death, and surviving patients have significant morbidity. The goal of ongoing research to elucidate the genetic causes of CDH is to develop better treatment and ultimately prevention. CDH is a complex developmental defect that is etiologically heterogeneous. This review summarizes the recurrent genetic causes of CDH including aneuploidies, chromosome copy number variants, and single gene mutations. It also discusses strategies for genetic evaluation and genetic counseling in an era of rapidly evolving technologies in clinical genetic diagnostics.

Expanding the phenotypic spectrum of PORCN variants in two males with syndromic microphthalmia

Variants in PORCN are a cause of Goltz-Gorlin syndrome or Focal Dermal Hypoplasia, an X-linked dominant disorder affecting heterozygous females and until now considered to be embryonic lethal in males. Exome sequencing was performed in a family in which two male siblings were characterized by microphthalmia and additional congenital anomalies including diaphragmatic hernia, spina bifida and cardiac defects. Surprisingly, we identified a maternally inherited variant in PORCN present in both males as well as in two female siblings. This represents the first finding of a PORCN variant in non-mosaic males affected with Goltz-Gorlin syndrome. The apparently asymptomatic mother showed extreme skewing of X-inactivation (90%), an asymptomatic female sibling showed skewing of 88%, and the second female sibling affected with cutis aplasia of the scalp showed X-inactivation considered within the normal range.

Development of the diaphragm -- a skeletal muscle essential for mammalian respiration

The mammalian diaphragm muscle is essential for respiration, and thus is one of the most critical skeletal muscles in the human body. Defects in diaphragm development leading to congenital diaphragmatic hernias (CDH) are common birth defects and result in severe morbidity or mortality. Given its functional importance and the frequency of congenital defects, an understanding of diaphragm development, both normally and during herniation, is important. We review current knowledge of the embryological origins of the diaphragm, diaphragm development and morphogenesis, as well as the genetic and developmental aetiology of diaphragm birth defects.

Focal dermal hypoplasia: updates

Focal dermal hypoplasia (FDH), or Goltz-Gorlin syndrome, is a rare syndrome and may result in multisystem disorders. Several reviews of FDH have been published. However, the last comprehensive review of this disorder appeared more than 20 years ago. To date, a number of new clinical manifestations have been reported and considerable knowledge has accumulated regarding etiology and pathogenetic mechanisms. The purpose of this review is to gather these more recent data and to provide organized and reliable information. So we reviewed 159 cases of FDH that had been reported from 1990 to 2012, summarized the new discoveries, and suggested a potential standard for the diagnosis of FDH. We also reported on a Chinese girl with FDH, who was clinically and histologically in accord with FDH, as an example.

Deletion of Porcn in mice leads to multiple developmental defects and models human focal dermal hypoplasia (Goltz syndrome)

BACKGROUND

Focal Dermal Hypoplasia (FDH) is a genetic disorder characterized by developmental defects in skin, skeleton and ectodermal appendages. FDH is caused by dominant loss-of-function mutations in X-linked PORCN. PORCN orthologues in Drosophila and mice encode endoplasmic reticulum proteins required for secretion and function of Wnt proteins. Wnt proteins play important roles in embryo development, tissue homeostasis and stem cell maintenance. Since features of FDH overlap with those seen in mouse Wnt pathway mutants, FDH likely results from defective Wnt signaling but molecular mechanisms by which inactivation of PORCN affects Wnt signaling and manifestations of FDH remain to be elucidated.

RESULTS

We introduced intronic loxP sites and a neomycin gene in the mouse Porcn locus for conditional inactivation. Porcn-ex3-7flox mice have no apparent developmental defects, but chimeric mice retaining the neomycin gene (Porcn-ex3-7Neo-flox) have limb, skin, and urogenital abnormalities. Conditional Porcn inactivation by EIIa-driven or Hprt-driven Cre recombinase results in increased early embryonic lethality. Mesenchyme-specific Prx-Cre-driven inactivation of Porcn produces FDH-like limb defects, while ectodermal Krt14-Cre-driven inactivation produces thin skin, alopecia, and abnormal dentition. Furthermore, cell-based assays confirm that human PORCN mutations reduce WNT3A secretion.

CONCLUSIONS

These data indicate that Porcn inactivation in the mouse produces a model for human FDH and that phenotypic features result from defective WNT signaling in ectodermal- and mesenchymal-derived structures.

Mutation update for the PORCN gene

Mutations in the PORCN gene were first identified in Goltz-Gorlin syndrome patients in 2007. Since then, several reports have been published describing a large variety of genetic defects resulting in the Goltz-Gorlin syndrome, and mutations or deletions were also reported in angioma serpiginosum, the pentalogy of Cantrell and Limb-Body Wall Complex. Here we present a review of the published mutations in the PORCN gene to date and report on seven new mutations together with the corresponding clinical data. Based on the review we have created a Web-based locus-specific database that lists all identified variants and allows the inclusion of future reports. The database is based on the Leiden Open (source) Variation Database (LOVD) software, and is accessible online at http://www.lovd.nl/porcn. At present, the database contains 106 variants, representing 68 different mutations, scattered along the whole coding sequence of the PORCN gene, and 12 large gene rearrangements, which brings up to 80 the number of unique mutations identified in Goltz-Gorlin syndrome patients.