Further delineation of auriculocondylar syndrome based on 14 novel cases and reassessment of 25 published cases.

Auriculocondylar syndrome (ACS) is a rare craniofacial disorder characterized by mandibular hypoplasia and an auricular defect at the junction between the lobe and helix, known as a "Question Mark Ear" (QME). Several additional features, originating from the first and second branchial arches and other tissues, have also been reported. ACS is genetically heterogeneous with autosomal dominant and recessive modes of inheritance. The mutations identified to date are presumed to dysregulate the endothelin 1 signaling pathway. Here we describe 14 novel cases and reassess 25 published cases of ACS through a questionnaire for systematic data collection. All patients harbor mutation(s) in PLCB4, GNAI3, or EDN1. This series of patients contributes to the characterization of additional features occasionally associated with ACS such as respiratory, costal, neurodevelopmental, and genital anomalies, and provides management and monitoring recommendations.

Osteogenesis imperfecta in Brazilian patients.

Osteogenesis Imperfecta (OI) is a heterogeneous genetic disorder characterized by bone fragility and fracture. Mutations in 20 distinct genes can cause OI, and therefore, the genetic diagnosis of OI is frequently difficult to obtain because of the great number of genes that can be related with this disease. Studies that report the most frequently mutated genes in OI patients can help to improve molecular strategies for diagnosis of the disease. In order to characterize the mutation profile of OI in Brazilian patients, we analyzed 30 unrelated patients through SSCP screening, NGS gene panel, and/or Sanger sequencing for the 11 most frequently mutated genes in the database of mutations, including COL1A1, COL1A2, P3H1, CRTAP, PPIB, SERPINH1, SERPINF1, FKBP10, SP7, WNT1 and IFITM5. Disease-causing variants were identified in COL1A1, COL1A2, FKBP10, P3H1, and IFITM5. A total of 28 distinct mutations were identified, including seven novel changes. Our data show that the analysis of these five genes is able to detect at least 95% of causative mutations in OI disorder from Brazilian population. However, it has to be taken into considerations that distinct populations can have different frequencies of disease-causing variants. Hence, it is important to replicate this study in other groups.

Craniofrontonasal Syndrome Caused by Introduction of a Novel uATG in the 5'UTR of EFNB1.

Craniofrontonasal syndrome (CFNS) is an X-linked disorder caused by EFNB1 mutations in which females are more severely affected than males. Severe male phenotypes are associated with mosaicism, supporting cellular interference for sex bias in this disease. Although many variants have been found in the coding region of EFNB1, only 2 pathogenic variants have been identified in the same nucleotide in 5'UTR, disrupting the stop codon of an upstream open reading frame (uORF). uORFs are known to be part of a wide range of post-transcriptional regulation processes, and just recently, their association with human diseases has come to light. In the present study, we analyzed EFNB1 in a female patient with typical features of CFNS. We identified a variant, located at c.-411, creating a new upstream ATG (uATG) in the 5'UTR of EFNB1, which is predicted to alter an existing uORF. Dual-luciferase reporter assays showed significant reduction in protein translation, but no difference in the mRNA levels. Our study demonstrates, for the first time, the regulatory impact of uATG formation on EFNB1 levels and suggests that this should be the target region in molecular diagnosis of CFNS cases without pathogenic variants in the coding and splice sites regions of EFNB1.

Evidence for DNA methylation mediating genetic liability to non-syndromic cleft lip/palate.

AIM: To determine if nonsyndromic cleft lip with or without cleft palate (nsCL/P) genetic risk variants influence liability to nsCL/P through gene regulation pathways, such as those involving DNA methylation. MATERIALS & METHODS: nsCL/P genetic summary data and methylation data from four studies were used in conjunction with Mendelian randomization and joint likelihood mapping to investigate potential mediation of nsCL/P genetic variants. RESULTS & CONCLUSION: Evidence was found at VAX1 (10q25.3), LOC146880 (17q23.3) and NTN1 (17p13.1), that liability to nsCL/P and variation in DNA methylation might be driven by the same genetic variant, suggesting that genetic variation at these loci may increase liability to nsCL/P by influencing DNA methylation. Follow-up analyses using different tissues and gene expression data provided further insight into possible biological mechanisms.

Large deletion in PIGL: a common mutational mechanism in CHIME syndrome?

Abstract CHIME syndrome is an extremely rare autosomal recessive multisystemic disorder caused by mutations in PIGL. PIGL is an endoplasmic reticulum localized enzyme that catalyzes the second step of glycosylphosphatidylinositol (GPI) biosynthesis, which plays a role in the anchorage of cell-surface proteins including receptors, enzymes, and adhesion molecules. Germline mutations in other members of GPI and Post GPI Attachment to Proteins (PGAP) family genes have been described and constitute a group of diseases within the congenital disorders of glycosylation. Patients in this group often present alkaline phosphatase serum levels abnormalities and neurological symptoms. We report a CHIME syndrome patient who harbors a missense mutation c.500T > C (p.Leu167Pro) and a large deletion involving the 5' untranslated region and part of exon 1 of PIGL. In CHIME syndrome, a recurrent missense mutation c.500T > C (p.Leu167Pro) is found in the majority of patients, associated with a null mutation in the other allele, including an overrepresentation of large deletions. The latter are not detected by the standard analysis in sequencing techniques, including next-generation sequencing. Thus, in individuals with a clinical diagnosis of CHIME syndrome in which only one mutation is found, an active search for a large deletion should be sought.

Large deletion in PIGL: a common mutational mechanism in CHIME syndrome?

CHIME syndrome is an extremely rare autosomal recessive multisystemic disorder caused by mutations in PIGL. PIGL is an endoplasmic reticulum localized enzyme that catalyzes the second step of glycosylphosphatidylinositol (GPI) biosynthesis, which plays a role in the anchorage of cell-surface proteins including receptors, enzymes, and adhesion molecules. Germline mutations in other members of GPI and Post GPI Attachment to Proteins (PGAP) family genes have been described and constitute a group of diseases within the congenital disorders of glycosylation. Patients in this group often present alkaline phosphatase serum levels abnormalities and neurological symptoms. We report a CHIME syndrome patient who harbors a missense mutation c.500T > C (p.Leu167Pro) and a large deletion involving the 5' untranslated region and part of exon 1 of PIGL. In CHIME syndrome, a recurrent missense mutation c.500T > C (p.Leu167Pro) is found in the majority of patients, associated with a null mutation in the other allele, including an overrepresentation of large deletions. The latter are not detected by the standard analysis in sequencing techniques, including next-generation sequencing. Thus, in individuals with a clinical diagnosis of CHIME syndrome in which only one mutation is found, an active search for a large deletion should be sought.

Cnbp ameliorates Treacher Collins Syndrome craniofacial anomalies through a pathway that involves redox-responsive genes.

Treacher Collins Syndrome (TCS) is a rare congenital disease (1:50 000 live births) characterized by craniofacial defects, including hypoplasia of facial bones, cleft palate and palpebral fissures. Over 90% of the cases are due to mutations in the TCOF1 gene, which codifies the nucleolar protein Treacle. Here we report a novel TCS-like zebrafish model displaying features that fully recapitulate the spectrum of craniofacial abnormalities observed in patients. As it was reported for a Tcof1+/- mouse model, Treacle depletion in zebrafish caused reduced rRNA transcription, stabilization of Tp53 and increased cell death in the cephalic region. An increase of ROS along with the overexpression of redox-responsive genes was detected; furthermore, treatment with antioxidants ameliorated the phenotypic defects of craniofacial anomalies in TCS-like larvae. On the other hand, Treacle depletion led to a lowering in the abundance of Cnbp, a protein required for proper craniofacial development. Tcof1 knockdown in transgenic zebrafish overexpressing cnbp resulted in barely affected craniofacial cartilage development, reinforcing the notion that Cnbp has a role in the pathogenesis of TCS. The cnbp overexpression rescued the TCS phenotype in a dose-dependent manner by a ROS-cytoprotective action that prevented the redox-responsive genes' upregulation but did not normalize the synthesis of rRNAs. Finally, a positive correlation between the expression of CNBP and TCOF1 in mesenchymal cells from both control and TCS subjects was found. Based on this, we suggest CNBP as an additional target for new alternative therapeutic treatments to reduce craniofacial defects not only in TCS but also in other neurocristopathies.

Intragenic Deletion in the LIFR Gene in a Long-Term Survivor with Stüve-Wiedemann Syndrome.

Stüve-Wiedemann syndrome (SWS, OMIM 601559) is a rare autosomal recessive bent-bone dysplasia, caused by loss-of-function mutations in the leukemia inhibitory factor receptor (LIFR) gene, which usually leads to early death. Only few patients with long-term survival have been described in the literature. We report on a 5-year-old boy from a consanguineous marriage with molecular analysis for the LIFR gene. Sanger and next-generation sequencing (NGS) of LIFR were performed. Copy number variation analysis with NGS showed a novel mutation as the cause for the syndrome: an intragenic homozygous deletion in LIFR, involving exons 15-20. Bridging PCR was carried out to confirm the intragenic deletion. This is the first description of a large deletion in LIFR, broadening the spectrum of mutations in SWS. Besides the reported allelic heterogeneity, further studies such as exome sequencing are required to identify a novel gene in order to confirm the locus heterogeneity in SWS.

Human fallopian tube mesenchymal stromal cells enhance bone regeneration in a xenotransplanted model.

We have recently reported that human fallopian tubes, which are discarded during surgical procedures of women submitted to sterilization or hysterectomies, are a rich source of human fallopian tube mesenchymal stromal cells (htMSCs). It has been previously shown that human mesenchymal stromal cells may be useful in enhancing the speed of bone regeneration. This prompted us to investigate whether htMSCs might be useful for the treatment of osteoporosis or other bone diseases, since they present a pronounced capacity for osteogenic differentiation in vitro. Based on this prior knowledge, our aim was to evaluate, in vivo, the osteogenic capacity of htMSCs to regenerate bone through an already described xenotransplantation model: nonimmunosuppressed (NIS) rats with cranial defects. htMSCs were obtained from five 30-50 years old healthy women and characterized by flow cytometry and for their multipotenciality in vitro capacity (osteogenic, chondrogenic and adipogenic differentiations). Two symmetric full-thickness cranial defects on each parietal region of seven NIS rats were performed. The left side (LS) of six animals was covered with CellCeram (Scaffdex)-a bioabsorbable ceramic composite scaffold that contains 60% hydroxyapatite and 40% ß-tricalciumphosphate-only, and the right side (RS) with the CellCeram and htMSCs (10(6) cells/scaffold). The animals were euthanized at 30, 60 and 90 days postoperatively and cranial tissue samples were taken for histological analysis. After 90 days we observed neobone formation in both sides. However, in animals euthanized 30 and 60 days after the procedure, a mature bone was observed only on the side with htMSCs. PCR and immunofluorescence analysis confirmed the presence of human DNA and thus that human cells were not rejected, which further supports the imunomodulatory property of htMSCs. In conclusion, htMSCs can be used successfully to enhance bone regeneration in vivo, opening a new field for future treatments of osteoporosis and bone reconstruction.

A rigorous approach to facilitate and guarantee the correctness of the genetic testing management in human genome information systems.

BACKGROUND: Recent medical and biological technology advances have stimulated the development of new testing systems that have been providing huge, varied amounts of molecular and clinical data. Growing data volumes pose significant challenges for information processing systems in research centers. Additionally, the routines of genomics laboratory are typically characterized by high parallelism in testing and constant procedure changes. RESULTS: This paper describes a formal approach to address this challenge through the implementation of a genetic testing management system applied to human genome laboratory. We introduced the Human Genome Research Center Information System (CEGH) in Brazil, a system that is able to support constant changes in human genome testing and can provide patients updated results based on the most recent and validated genetic knowledge. Our approach uses a common repository for process planning to ensure reusability, specification, instantiation, monitoring, and execution of processes, which are defined using a relational database and rigorous control flow specifications based on process algebra (ACP). The main difference between our approach and related works is that we were able to join two important aspects: 1) process scalability achieved through relational database implementation, and 2) correctness of processes using process algebra. Furthermore, the software allows end users to define genetic testing without requiring any knowledge about business process notation or process algebra. CONCLUSIONS: This paper presents the CEGH information system that is a Laboratory Information Management System (LIMS) based on a formal framework to support genetic testing management for Mendelian disorder studies. We have proved the feasibility and showed usability benefits of a rigorous approach that is able to specify, validate, and perform genetic testing using easy end user interfaces.

Beare-Stevenson syndrome: Two South American patients with FGFR2 analysis.

We report two patients with Beare-Stevenson syndrome. This syndrome presents craniosynostosis with or without clover-leaf skull, craniofacial anomalies, cutis gyrata, acanthosis nigricans, prominent umbilical stump, furrowed palms and soles, genital and anal anomalies. Both female newborn patients presented at birth with craniofacial anomalies, variable cutis gyrata in forehead and preauricular regions, prominent umbilical stump and anogenital anomalies. Furrowed palms and soles were also observed. The radiologic examination showed a cloverleaf-form craniosynostosis. Chromosomes were normal. They were born with respiratory distress and were connected to mechanical ventilation for ventilatory support. Both of them died in 50 days after birth due to secondary complications. The molecular analysis of these patients identified the mutation Tyr375Cys in the FGFR2 gene.