Genetic and functional analyses detect one pathological NFATC1 mutation in a Chinese tricuspid atresia family.

BACKGROUND: Cardiac valvulogenesis is a highly conserved process among vertebrates and cause unidirectional flow of blood in the heart. It was precisely regulated by signal pathways such as VEGF, NOTCH, and WNT and transcriptional factors such as TWIST1, TBX20, NFATC1, and SOX9. Tricuspid atresia refers to morphological deficiency of the valve and confined right atrioventricular traffic due to tricuspid maldevelopment, and is one of the most common types of congenital valve defects. METHODS: We recruited a healthy couple with two fetuses aborted due to tricuspid atresia and identified related gene mutations using whole-exome sequencing. We then discussed the pathogenic significance of this mutation by bioinformatic and functional analyses. RESULTS: PROVEAN, PolyPhen, MutationTaster, and HOPE indicated the mutation could change the protein function and cause disease; Western blotting showed the expression of NFATC1 c.964G>A mutation was lower than the wild type. What's more, dual-luciferase reporter assay showed the transcriptional activity of NFATC1 was impact by mutation and the expression of downstream DEGS1 was influenced. CONCLUSION: Taken together, the c.964G>A mutation might be pathological and related to the occurrence of disease. Our research tended to deepen the understanding of etiology of tricuspid atresia and gene function of NFATC1, and provide some references or suggestions for genetic diagnosis of tricuspid atresia.

The VANGL1 P384R variant cause both neural tube defect and Klippel-Feil syndrome.

BACKGROUND: Neural tube defect (NTD) is a common birth defect causing much death in the world. Variants in VANGL1 lead to NTD and caudal regression syndrome. NTD displays a complex phenotype encompassing both genetic and environmental factors. METHODS: The fetus was diagnosed by prenatal ultrasound examination. Postnatal CT and autopsy were performed. Genetic testing was conducted in the family and Sanger sequencing was validated. Multiple prediction soft-wares were used to predict the pathogenicity of the variant. RESULTS: The VANGL1 gene variant c.1151C>G (P384R) was detected in a fetus diagnosed with tethered spinal cord and sacrococcygeal lipoma. The VANGL1 variant c.1151C>G (P384R) was reported in a Klippel-Feil syndrome patient. The VANGL1 variant was validated in the trio-family but the mother showed no abnormalities. CONCLUSION: Overall, this study presents fetal NTD caused by the same VANGL1 variant found in a Klippel-Feil syndrome patient with complete clinical information of prenatal ultrasound, postnatal CT, and genetic results as early as 25 GW. Our study not only expands the VANGL1 mutational spectrum but also sheds light on the important role of the VANGL1 P384R variant in human development.

Non-classic splicing mutation in the CPLANE1 (C5orf42) gene cause Joubert syndrome in a fetus with severe craniocerebral dysplasia.

BACKGROUD: Joubert syndrome is a rare neurodevelopmental disorder characterized by clinical and genetic heterogeneity. The characteristic molar tooth sign, which resulted from cerebellar vermis hypoplasia and midbrain anomalies, is expected to be the key diagnostic feature for this disease. However, it is not easy to make a definite diagnosis in prenatal only based on the imageology due to its clinical heterogeneity. CASE REPORT: We report on a fetus who was detected cerebellum dysplasia and encephalocele by ultrasound at 19 and 23 gestational weeks and confirmed by MRI examination. The pregnancy was terminated at 23 weeks of gestation. Postaxial polydactyly and deficiency in occipital bone and skin were identified in the induced fetus. RESULTS: The whole exome sequencing identified a novel compound heterozygous variation in the CPLANE1 gene related with Joubert syndrome, including a 2-bp insertion, NM_023073.3:c.1383_1384dup; p.(Gly462Glufs*3) and a non-classic splicing variation, NC_000005.10(NM_023073.3):c.7691-5_7691-4del. The pathogenicity of the non-classic splicing variation was further confirmed by cDNA level sequencing, which showed a exon 39 skipping that would introduce a premature termination. The novel compound heterozygous variation caused a complete function loss of the CPLANE1 gene. CONCLUSION: The cerebellum dysplasia fetus without obvious molar tooth sign was finally diagnosed as Joubert syndrome, combined with genetic detecting and the postnatal clinical symptoms. We also highlight the clinical heterogeneity of encephalodysplasia in Joubert syndrome, which increases the clinical diagnosis difficulty, especially for prenatal diagnosis. Our findings provided a new perspective for the prenatal diagnosis of Joubert syndrome with severe craniocerebral dysplasia and expanded the variation spectrum of the CPLANE1 gene.

Loss-of-function or gain-of-function variations in VINCULIN (VCL) are risk factors of human neural tube defects.

BACKGROUND: Neural tube defects (NTDs) are severe birth defects resulting from the failure of neural tube closure during embryogenesis. Both genetic and environmental factors contribute to the occurrence of NTDs and the heritability of NTDs is approximately 70%. As a key component of focal adhesions, Vinculin (VCL) plays pivotal roles in cell skeleton remodeling and signal transduction. Vcl deficient mice displayed NTD, but how VCL variants contribute to human NTDs has not been addressed yet. METHODS: We screened VCL variants in a Chinese cohort of 387 NTDs and 244 controls by targeted next-generation sequencing. RESULTS: We identified four case-specific VCL variations (p.M209L, p.D256fs, p.L555V and p.R586Q). VCL p.D256fs and p.L555V are novel variations that have never been reported. Our analysis revealed that p.D256fs is a loss-of-function variant, while p.L555V showed a gain of function in planner cell polarity (PCP) pathway regulation and cell migration, probably due to its enhanced protein stability. CONCLUSION: Our study reports human NTD specific novel variations in VCL and provides the functional evaluation of VCL variants related to the etiology of human NTDs.

TP63-mutation as a cause of prenatal lethal multicystic dysplastic kidneys.

BACKGROUND: Ectrodactyly-ectodermal dysplasia-clefting syndrome 3 (EEC) is one of the six overlapping syndromes caused by mutations in the tumor protein p63 gene (TP63). EEC is suspected when patients have cleft hands or feet, polydactyly, and syndactyly, abnormal development of the ectodermally derived structures, and orofacial clefting. Genitourinary (GU) anomalies have been identified in patients with EEC, yet these are often under-recognized and under-reported. The available literature on sonographic prenatal findings is sparse, especially when considering GU anomalies. METHODS: We present the case of a male stillborn fetus, who was found antenatally to have multicystic dysplastic kidneys and anhydramnios. Following the termination of pregnancy, examination and autopsy further revealed unilateral polydactyly and bilateral syndactyly which had not been previously identified on antenatal ultrasound. RESULTS: Whole-exome sequencing (WES) revealed a de novo heterozygous pathogenic variant in exon 5 of the TP63 gene: p.His247Arg: c.740A>G (NM_003722.4) which has been reported in the literature. The His247Arg variant has been published as a pathogenic variant in association with EEC, both with and without orofacial clefting. CONCLUSION: Our prenatal case expands the phenotypic spectrum of TP63-related disorders in general. In addition, it adds to the phenotype associated with the His247Arg pathogenic variant responsible for EEC. Further, we highlight the importance of WES as a postnatal tool to help clarify unexpected findings, and as a way to add to the spectrum of existing phenotypes of known single-gene disorders.

Monochorionic diamniotic twins of discordant external genitalia with 45,X/46,XY mosaicism.

BACKGROUND: Monozygotic twins with 45,X/46,XY mosaicism, discordant for phenotypic sex, are extremely rare. METHODS: This report describes the clinical findings of a rare case of 45,X/46,XY mosaicism in monozygotic twins with different external genitalia. Single nucleotide polymorphism (SNP) array analysis, performed by collecting DNA from each umbilical cord, showed identical SNPs in the autosomal chromosomes of both fetuses. RESULTS: Chorionic villus sampling of a 37-year-old primigravida carrying monozygotic twins revealed a 45,X/46,XY karyotype. Autopsy of the aborted fetuses revealed a penis and testes on one fetus and a vagina, uterus, and ovaries in the other fetus--which also had severe cystic hygroma. Cell counting using fluorescence in situ hybridization with XY probes (XY-FISH) showed 20% and 80% abundance of 45,X cells in the internal genitalia, liver, heart, lung, adrenal gland, bone marrow, and spine of the male and female fetuses, respectively. CONCLUSION: These results indicated that the fetuses were genetically monozygotic twins and their different degrees of mosaicism may have resulted in different genital phenotypes.

Bronchogenic cyst presenting as content of omphalocele - A case report.

Bronchogenic cyst (BC) is a very rare congenital anomaly occurring due to budding of the primitive foregut, and its common location is the posterior mediastinum. BC when diagnosed prenatally can be treated if it is encroaching on the development of lungs. BC has been reported in other locations such as cervical, thoracic, abdominal sites and also as subcutaneous lesions. Omphalocele is a congenital malformation occurring due to a central defect in the abdominal wall with herniation of the viscera. The nonentity documented here was found in a female fetus with 20 weeks of gestational age. The mother was a primigravida who had antenatal ultrasound scan rendering diagnosis of a live fetus having abdominal wall defect with omphalocele. This case is exceptionally rare as the content of omphalocele was BC having a classical wall lined by pseudostratified ciliated columnar epithelium overlying band-like cartilage. The extensive search in the literature did not reveal another similar case.

Characterization of three ciliopathy pedigrees expands the phenotype associated with biallelic C2CD3 variants.

Whole exome sequencing (WES) is utilized in diagnostic odyssey cases to identify the underlying genetic cause associated with complex phenotypes. Recent publications suggest that WES reveals the genetic cause in ~25% of these cases and is most successful when applied to children with neurological disease. The residual 75% of cases remain genetically elusive until more information becomes available in the literature or functional studies are pursued. WES performed on three families with presumed ciliopathy diagnoses, including orofaciodigital (OFD) syndrome, fetal encephalocele, or Joubert-related disorder, identified compound heterozygous variants in C2CD3. Biallelic variants in C2CD3 have previously been associated with ciliopathies, including OFD syndrome type 14 (OFD14; MIM: 615948). As three of the six identified variants were predicted to affect splicing, exon-skipping analysis using either RNA sequencing or PCR-based methods were completed to determine the pathogenicity of these variants, and showed that each of the splicing variants led to a frameshifted protein product. Using these studies in combination with the 2015 ACMG guidelines, each of the six identified variants were classified as either pathogenic or likely pathogenic, and are therefore likely responsible for our patients' phenotypes. Each of the families had a distinct clinical phenotype and severity of disease, extending from lethal to viable. These findings highlight that there is a broad phenotypic spectrum associated with C2CD3-mediated disease and not all patients present with the typical features of OFD14.

New splicing pathogenic variant in EBP causing extreme familial variability of Conradi-Hünermann-Happle Syndrome.

X-linked dominant chondrodysplasia punctata (CDPX2 or Conradi-Hünermann-Happle syndrome, MIM #302960) is caused by mutations in the EBP gene. Affected female patients present with Blaschkolinear ichthyosis, coarse hair or alopecia, short stature, and normal psychomotor development. The disease is usually lethal in boys. Nevertheless, few male patients have been reported; they carry a somatic mosaicism in EBP or present with Klinefelter syndrome. Here, we report CDPX2 patients belonging to a three-generation family, carrying the splice variant c.301 + 5 G > C in intron 2 of EBP. The grandfather carries the variant as mosaic state and presents with short stature and mild ichthyosis. The mother also presents with short stature and mild ichthyosis and the female fetus with severe limb and vertebrae abnormalities and no skin lesions, with random X inactivation in both. This further characterizes the phenotypical spectrum of CDPX2, as well as intrafamilial variability, and raises the question of differential EBP mRNA splicing between the different target tissues.

First fetal case of the 8q24.3 contiguous genes syndrome.

Molecular cytogenetics, particularly array-CGH, opened the way to the « genotype first approach ¼ and for the discovery of new micro rearrangement syndromes. This was the case for the 8q24.3 microdeletion syndrome. Here, we describe the phenotype of a fetus with a 8q24.3 deletion. This rare condition has to be considered as a contiguous genes syndrome because its phenotype is generated by the SCRIB and PUF60 adjacent gene endophenotypes. The fetus presented atrioventricular septal defect and hypoplastic aortic arch, facial dysmorphism, microretrognathia, dysmorphic ears, clinodactyly of the 5th digit on both hands, mild rocker bottom feet and abnormal third sacral vertebra. This fetus is the first case where the endophenotype produced by SCRIB gene is absent. This case is compared with the previous published cases.

[Prenatal diagnosis of central nervous system malformations]. / A központi idegrendszer fejlodési rendellenességeinek praenatalis diagnosztikája.

The prenatal diagnosis of fetal malformations have been the subject of numerous publications in the literature. This has dramatically increased in the last 15 years, mainly due to the advent of high-resolution ultrasound. In addition adequate guidelines issued by professional organizations have encouraged the universal approach to the imaging of fetal anatomy as well as malformations. One of the most significant groups of the fetal anomalies is the central nervous system malformation. Due to its prevalence and severity the praenatal diagnostics of central nervous system malformations got basic significance. In this review we attempted to summarize the recent informations concerning the prenatal diagnostics of the central nervous system anomalies.

Mola hidatiforme parcial / Partial hydatidiform mole

Introducción: el término enfermedad trofoblástica gestacional es una anormal proliferación del trofoblasto, que desde el punto de vista histológico se clasifica en mola hidatiforme, mola invasora, coriocarcinoma y tumor del sitio de implantación del trofoblasto. Objetivo: describir las características clínicas y ultrasonográficas de una mola hidatiforme parcial o mola embrionada. Paciente: se presenta un caso de 24 sem de gestación con el diagnóstico ultrasonográfico de mola hidatidiforme parcial. Resultados: se realizó cariotipo fetal y determinación de niveles de gonadotropina coriónica en suero materno. Se hallaron defectos congénitos en el feto, por lo que se ofreció asesoramiento genético a la pareja, que optó por la interrupción de la gestación. Conclusiones: el diagnóstico prenatal fue confirmado por la anatomía patológica

Introduction: the term gestational trophoblastic disease is an abnormal proliferation of the trophoblast, which is histologically classified as hydatidiform mole, invasive mole, choriocarcinoma, and tumor trophoblast implantation site. Objective: to describe the clinical and ultrasonographic partial hydatidiform mole or mole embrionada. Patient: we report a 24- week - prenancy case with ultrasonographic diagnosis of partial hydatidiform mole. Results: fetal karyotype was performed and levels of chorionic gonadotropin in maternal serum were determined. We found congenital defects in the fetus, so genetic counseling was offered to the parents, who chose ending this pregnancy. Conclusions: the prenatal diagnosis was confirmed by pathology

Intrapancreatic accessory spleen.

A case of accessory spleen located in the tail of the pancreas in a stillbirth male foetus is reported. The congenital anomaly was revealed at autopsy. The intrapancreatic spleen was well demarcated and was composed of red and white pulp; however, same pancreatic ducts were intermingled with the splenic parenchyma. As well as the intrapancreatic lesion another minute accessory spleen was also found at the hilum of the proper organ. Since a lack of morphological features of trisomy 13 syndrome were found in the foetus, the ectopic spleens were regarded as incidental findings.

Is it always possible to determine a diagnosis? Prenatal ultrasonography, post mortem magnetic resonance, autopsy.

Pathological-anatomical autopsy is the gold standard for determining of foetal abnormalities, but in some cases its role is limited (pathology of central nervous system, in particular, in case of ventricular dilatation or developed autolysis). In pathology of central nervous system, where insufficiency of autopsy can occur, additional post mortem magnetic resonance imaging (MRI) is performed to determine type of malformation. In this case report, we would like to point out the fact that although all investigating methods including post mortem magnetic resonance and autopsy (incl. imunohistochemical tests) are used, this need not necessarily result in a clear diagnostic conclusion of the aborted foetus. Post mortem MRI visualized pathology: dilatation of both lateral ventricals, more in the left and, above all, a pathological focus parasagittaly on the right with haemorrhage and cystic component; it raised a suspicion on ependymoma. However imunohistochemical test did not give an unambiguous conclusion; therefore diagnosis based on MRI could not be uniquely verified.

Nuchal translucency and lymphatic system maldevelopment.

We describe the histological examination of 18 aborted fetuses that had increased nuchal translucency (NT) between 11(+0) and 13(+6) weeks' gestation. The aim of this study was to assess the corresponding NT anatomic features by immunohistochemical (IHC) investigation. A morphological study was performed using lymphatic and blood endothelial specific markers, as well as smooth muscle actin (SMA). We found that all 18 cases were D2-40 positive, CD31 positive, and CD34 negative, suggesting the presence of nuchal lymph vessel ectasia. We found that 12/18 cases were SMA staining positive and 6/18 cases were SMA negative, suggesting that 6/18 cases had nuchal cystic lymphangiectasia, whereas 12/18 had cystic hygromas. The present data seem to confirm the reasonable hypothesis that lymphangiogenesis plays a relevant role in nuchal edema, increased NT, and that increased NT is the result of a lymphatic malformation or a delayed development of the lymphatic system.

Craniorachischisis totalis: a case report and review of the literature.

OBJECTIVE: To discuss a fetus with craniorachischisis diagnosed antenatally and to review the literature. METHOD: Case report. RESULTS: Craniorachischisis was detected on ultrasound scan in a fetus at gestational week 13. Pregnancy was terminated and diagnosis was verified postnatally. CONCLUSION: Craniorachischisis is a rare and severe form of neural tube defects (NTDs). The majority of currently known cases of mouse craniorachischisis have been found to result from disturbance of a single molecular signaling cascade, called planar cell polarity pathway (PCP). The mutant genes that have been causative in disturbance of PCP in mouse models have been examined in human malformations but none of them have so far been implicated in human craniorachischisis. To date, no other genes except the gene encoding 5,10-methylenetetrahydrofolate reductase have been specifically implicated in predisposition to NTDs. We suggest that other PCP genes should be considered as candidates for a role in the etiology of human NTDs. Further investigations are therefore necessary.

Association between exposure to emissions from the oil and gas industry and pathology of the immune, nervous, and respiratory systems, and skeletal and cardiac muscle in beef calves.

To determine potential associations between emissions from oil and gas field facilities and the risk of lesions in the immune, nervous, and respiratory systems of beef calves, researchers examined tissue samples collected from 1,531 cases with exposure data, which included aborted fetuses, stillbirths, and calf mortalities from 203 cow-calf herds, by means of histopathology. The researchers prospectively measured exposure to sulfur dioxide, hydrogen sulfide, and volatile organic compounds by using air-monitoring data from passive monitors. They used the density of facilities surrounding each pasture as a second measure of exposure. Each tissue was classified by the presence or absence of a series of specified lesions, including those associated with degeneration, necrosis, infection, inflammation, anomaly, lympholysis (for lymphoid tissue), and proliferation (for the respiratory system). Exposure was not associated with the risk of lesions to tissues of either the immune or nervous system in calves that were aborted or died in spring 2002. Exposures to sulfur dioxide and hydrogen sulfide were not significantly associated with the risk of lesions to respiratory tissues in calves that were born alive in spring 2002. Increasing postnatal exposures to volatile organic compounds measured as benzene and toluene were associated with increased odds of respiratory lesions. The association between volatile organic compounds measured as benzene and respiratory lesions was significant for calves older than 3 weeks. During gestation, increasing exposure to sulfur dioxide was associated with increased odds of lesions in either the skeletal muscle or myocardium.

Prenatal diagnosis of fetal exencephaly associated with amniotic band sequence at 17 weeks of gestation by fetal magnetic resonance imaging.

We report a fetus with exencephaly diagnosed by fetal magnetic resonance imaging (MRI) at 17 weeks of gestation. Fetal ultrasound performed at 13 and 17 weeks of gestation suggested occipital encephalocele. However, the fetal MRI done at 17 weeks of gestation showed exencephaly and suggested amniotic bands as the cause. By providing early and precise information regarding the abnormality and the possible etiology, the fetal MRI enabled us to provide the couple and their families with accurate information regarding the low recurrence risk of this condition.

Dysplastic cortical hyperostosis (Kozlowski-Tsuruta syndrome): report of a second case.

We report a fetus from a pregnancy that was terminated at 26 weeks gestation for hydrops and short limb skeletal dysplasia. The parents were first cousins. Post mortem examination showed pulmonary hypoplasia and hepatomegaly. The radiographs showed shortening and cortical thickening of all long bones. The cortical thickening was most marked in the long bones, ribs, clavicles and scapulae but spared the skull vault, facial bones and pelvis. There were coronal clefts in the lower lumbar vertebrae. The clinical and radiological features of this fetus conform to those reported in a stillborn male by Kozlowski and Tsuruta in 1989 (Br J Radiol 62:376-378). This is the second reported case of this condition and confirms that it is a distinct and recognisable, lethal skeletal dysplasia. The parental consanguinity in our patient suggests that this condition may be inherited in an autosomal recessive manner.