Transcriptomic analysis reveals mitochondrial dysfunction in the pathogenesis of Nager syndrome in sf3b4-depleted zebrafish.

Nager syndrome (NS) is a rare acrofacial dysostosis caused by heterozygous loss-of-function variants in the splicing factor 3B subunit 4 (SF3B4). The main clinical features of patients with NS are characterized by facial-mandibular and preaxial limb malformations. The migration and specification of neural crest cells are crucial for craniofacial development, and mitochondrial fitness appears to play a role in such processes. Here, by analyzing our previously published transcriptome dataset, we aim to investigate the potential involvement of mitochondrial components in the pathogenesis of craniofacial malformations, especially in sf3b4 mutant zebrafish. We identified that oxidative phosphorylation (OXPHOS) defects and overproduction of reactive oxygen species (ROS) due to decreased antioxidants defense activity, which leads to oxidative damage and mitochondrial dysfunction. Furthermore, our results highlight that fish lacking sf3b4 gene, primarily display defects in mitochondrial complex I. Altogether, our findings suggest that mitochondrial dysfunction may contribute to the development of the craniofacial anomalies observed in sf3b4-depleted zebrafish.

AI-based diagnosis in mandibulofacial dysostosis with microcephaly using external ear shapes.

Introduction: Mandibulo-Facial Dysostosis with Microcephaly (MFDM) is a rare disease with a broad spectrum of symptoms, characterized by zygomatic and mandibular hypoplasia, microcephaly, and ear abnormalities. Here, we aimed at describing the external ear phenotype of MFDM patients, and train an Artificial Intelligence (AI)-based model to differentiate MFDM ears from non-syndromic control ears (binary classification), and from ears of the main differential diagnoses of this condition (multi-class classification): Treacher Collins (TC), Nager (NAFD) and CHARGE syndromes. Methods: The training set contained 1,592 ear photographs, corresponding to 550 patients. We extracted 48 patients completely independent of the training set, with only one photograph per ear per patient. After a CNN-(Convolutional Neural Network) based ear detection, the images were automatically landmarked. Generalized Procrustes Analysis was then performed, along with a dimension reduction using PCA (Principal Component Analysis). The principal components were used as inputs in an eXtreme Gradient Boosting (XGBoost) model, optimized using a 5-fold cross-validation. Finally, the model was tested on an independent validation set. Results: We trained the model on 1,592 ear photographs, corresponding to 1,296 control ears, 105 MFDM, 33 NAFD, 70 TC and 88 CHARGE syndrome ears. The model detected MFDM with an accuracy of 0.969 [0.838-0.999] (p < 0.001) and an AUC (Area Under the Curve) of 0.975 within controls (binary classification). Balanced accuracies were 0.811 [0.648-0.920] (p = 0.002) in a first multiclass design (MFDM vs. controls and differential diagnoses) and 0.813 [0.544-0.960] (p = 0.003) in a second multiclass design (MFDM vs. differential diagnoses). Conclusion: This is the first AI-based syndrome detection model in dysmorphology based on the external ear, opening promising clinical applications both for local care and referral, and for expert centers.

Assessing craniofacial growth and form without landmarks: A new automatic approach based on spectral methods.

We present a novel method for the morphometric analysis of series of 3D shapes, and demonstrate its relevance for the detection and quantification of two craniofacial anomalies: trigonocephaly and metopic ridges, using CT-scans of young children. Our approach is fully automatic, and does not rely on manual landmark placement and annotations. Our approach furthermore allows to differentiate shape classes, enabling successful differential diagnosis between trigonocephaly and metopic ridges, two related conditions characterized by triangular foreheads. These results were obtained using recent developments in automatic nonrigid 3D shape correspondence methods and specifically spectral approaches based on the functional map framework. Our method can capture local changes in geometric structure, in contrast to methods based, for instance, on global shape descriptors. As such, our approach allows to perform automatic shape classification and provides visual feedback on shape regions associated with different classes of deformations. The flexibility and generality of our approach paves the way for the application of spectral methods in quantitative medicine.

Masticatory Efficiency in Orthodontic Patients with Craniofacial Disorder.

This study evaluates the masticatory efficiency in patients with craniofacial disorders (CD) compared to controls (C). A total of 119 participants (7-21 years), divided into CD group (n = 42, mean age 13.45 ± 5.2 years) and C group (n = 77, mean age 14.3 ± 3.27 years) under an orthodontic treatment were included. Masticatory efficiency was assessed using a standard food model test. The masticated food was examined according to its number of particles (n) and area (mm2), wherein a higher number of particles alongside a smaller area was an indication of better masticatory efficiency. Additionally, the influence of cleft formation, chewing side, dentition stage, age and sex were evaluated. Patients with CD chewed the standardized food in fewer particles (nCD = 61.76 vs. nC = 84.58), with a significantly higher amount of area than the controls (ACD = 192.91 mm2 vs. AC = 146.84 mm2; p = 0.04). In conclusion, patients with CD showed a significantly decreased mastication efficiency compared to healthy patients. Factors such as stage of cleft formation, chewing side, dentition stage and age showed an influence on masticatory efficiency, whereas no gender effect on the masticatory efficiency of CD patients was found.

Tessier's Cleft Number 6 Revisited: A Series of 26 new Cases and Literature Review of 44.

OBJECTIVE: To fix a gray zone left in Tessier's classification of rare clefts with cleft 6 and to give a more comprehensive description of cleft 6 anatomy. DESIGN: The material used for the research was a series of 26 clinical cases of patients with assessed cleft 6 and 44 cases found out of a literature review with enough data to be useful. The 70 cases were cross-examined by the authors. STUDY SETTING: The authors are senior craniofacial surgeons working in high-case load department from university centers where the patients are documented and receive primary as well as secondary treatment and follow-up. PATIENTS: The patients were selected out of the series of craniofacial deformities taken care of by the authors' department as rare clefts. MAIN OUTCOME: We describe the full spectrum of cleft 6 as an autonomous entity that could present itself in three subtypes: 6a is the most proximal and could be associated with cleft 8. The subtype 6b is medial toward the zygomatic arch and frequently associated with a bone and teeth appendage (frequently described as a "maxillary duplication"). The subtype 6C goes toward the external ear between the helix crus and the auditory meatus. CONCLUSIONS: The Tessier's opinion is that Treacher Collins syndrome was the association of clefts 6, 7, and 8 and is no longer sustainable in the light of modern genetics. Most of the cleft 6 are misdiagnosed in the literature.

SF3B4 Frameshift Variants Represented a More Severe Clinical Manifestation in Nager Syndrome.

Nager syndrome (NS) is a rare disease marked with craniofacial and preaxial limb anomalies. In this report, we summarized the current evidence to determine a possible genotype-phenotype association among NS individuals. Twenty-four articles comprising of 84 NS (including 9 patients with a severe form of NS [Rodriguez syndrome]) patients were examined, of which 76% were caused by variants in SF3B4 (OMIM *605593, Splicing Factor 3B, Subunit 4). Within the SF3B4 gene, variants located in exon 3 commonly occurred (20%) from a total identified variant, while hotspot location was identified in exon 1 (12%), and primarily occurred as frameshift variants (64%). Thirty-five distinct pathogenic variants within SF3B4 gene were identified with two common sites, c.1A > G and c.1060dupC in exons 1 and 5, respectively. Although no significant genotype-phenotype association was found, it is notable that patients with frameshift SF3B4 variants and predicted to lead to nonsense-mediated RNA decay (NMD) of the transcripts tended to have a more severe clinical manifestation. Additionally, patients harboring variants in exons 2 and 3 displayed a higher proportion of cardiac malformations. Taken together, this article summarizes the pathogenic variants observed in SF3B4 and provides a possible genotype-phenotype relationship in this disease.

Síndrome del incisivo central maxilar único: reporte de caso

El síndrome del incisivo central maxilar único es una rara alteración en el desarrollo y formación de órganos ubicados principalmente en la línea media; el cual ocurre de manera temprana entre los días 35 al 38 de vida intrauterina. Su etiología es desconocida, aunque se ha asociado a deleciones de los cromosomas 7 (7q.36.1) y 8, y a mutaciones en el gen Sonic Hedgehog. Presenta una prevalencia de 1/50.000 nacidos vivos y aunque es una anomalía poco frecuente del desarrollo craneofacial, su diagnóstico y tratamiento temprano son importantes para los odontólogos generales o especialistas ya que puede ser un signo de otras anomalías congénitas o del desarrollo graves. Por lo tanto, el objetivo de este caso es reportar la fase inicial de tratamiento en un niño con el síndrome de incisivo central maxilar único quien no había sido diagnosticado anteriormente con este síndrome. Caso Clínico: Paciente masculino de 10 años de edad, procedente de Jamundí, Valle del Cauca- Colombia. Reporta ausencia de órgano dentario superior. En el examen intraoral se observa un incisivo central único sobre la línea media del maxilar, ausencia de frenillo labial y papila incisiva, paladar oval y retrognatismo mandibular. Fue tratado en una primera fase con ortopedia funcional maxilar para mejorar la clase II y está a la espera de iniciar la segunda fase de tratamiento con ortodoncia. Conclusiones: El síndrome de incisivo central maxilar único es un síndrome poco frecuente el cual conlleva múltiples afecciones que interfieren en el normal desarrollo y crecimiento de estructuras anatómicas.

A síndrome do incisivo central superior único é uma alteração rara no desenvolvimento e formação de órgãos localizados principalmente na linha média; que ocorre precocemente entre os dias 35 a 38 de vida intrauterina. Sua etiologia é desconhecida, embora tenha sido associada a deleções dos cromossomos 7 (7q.36.1) e 8, e mutações no gene Sonic Hedgehog. Tem uma prevalência de 1/50.000 nascidos vivos e, embora seja uma anomalia rara do desenvolvimento craniofacial, seu diagnóstico e tratamento precoces são importantes para dentistas gerais ou especialistas, pois pode ser sinal de outras anomalias congênitas ou de desenvolvimento graves. Portanto, o objetivo deste caso é relatar a fase inicial do tratamento em uma criança com síndrome do incisivo central superior único que não havia sido previamente diagnosticada com essa síndrome. Caso clínico: Paciente do sexo masculino, 10 anos, procedente de Jamundí, Valle del Cauca- Colômbia. Relata ausência de órgão dentário superior. O exame intraoral mostra um único incisivo central na linha média maxilar, ausência de frênulo labial e papila incisiva, palato oval e retrognatismo mandibular. Foi tratado numa primeira fase com ortopedia funcional maxilar para melhorar a classe II e aguarda para iniciar a segunda fase do tratamento ortodôntico. Conclusões: A síndrome do incisivo central superior único é uma síndrome rara que envolve múltiplas condições que interferem no desenvolvimento e crescimento normal das estruturas anatômicas.

Solitary maxillary central incisor syndrome is a rare alteration in the development and formation of organs located mainly in the midline; which occurs early between days 35 to 38 of intrauterine life. Its etiology is unknown, although it has been associated with deletions of chromosomes 7 (7q.36.1) and 8, and mutations in the Sonic Hedgehog gene. It has a prevalence of 1/50,000 live births and although it is a rare anomaly of craniofacial development, its early diagnosis and treatment are important for general dentists or specialists since it can be a sign of other serious congenital or developmental anomalies. Therefore, the objective of this case is to report the initial phase of treatment in a child with solitary maxillary central incisor syndrome who had not been previously diagnosed with this syndrome. Clinical case: Male patient, 10 years old, from Jamundí, Valle del Cauca- Colombia. Reports absence of upper dental organ. Intraoral examination shows a solitary central incisor on the maxillary midline, absence of labial frenulum and incisive papilla, oval palate and mandibular retrognathism. He was treated in a first phase with maxillary functional orthopedics to improve class II and is waiting to start the second phase of orthodontic treatment. Conclusions: Solitary maxillary central incisor syndrome is a rare syndrome which involves multiple conditions that interfere with the normal development and growth of anatomical structures.

Craniofacial Malformations as Fundamental Diagnostic Tools in Syndromic Entities.

Background: A long list of syndromic entities can be diagnosed immediately through scrutinizing the clinical phenotype of the craniofacial features. The latter should be assisted via proper radiological interpretations. Patients and Methods: Different children aged from 1 month to 12 years were referred to our departments seeking orthopedic advice. Primarily, all received variable false diagnoses in other institutes. Two unrelated boys of one month and 12 months were falsely diagnosed as having positional plagiocephaly associated with contractures of idiopathic origin. Two unrelated boys of 14 months and 2 years were diagnosed with pseudo-hydrocephalus and non-specific syndrome, and were referred to explore their skeletal development. Two unrelated girls of 4 years old and 12 years old presented with multiple contractures were referred because of progressive scoliosis. A 4-year-old girl was referred with a false provisional diagnosis of facial diplegia. All children underwent detailed clinical, radiological and tomographic phenotypic characterizations and genetic testing, respectively. Results: Idaho syndrome (craniosynostosis associated with multiple dislocations) was the final diagnosis in the two unrelated boys with plagiocephaly and multiple contractures. Two children falsely diagnosed with pseudo-hydrocephalus and non-specific syndrome, were diagnosed with Silver-Russell syndrome (RSS). Contractural arachnodactyly Beals (CAB) was confirmed as the definitive diagnosis in the two unrelated girls with progressive scoliosis and multiple contractures. Parry-Romberg syndrome (PRS) associated with congenital lumbar kyphosis was the final diagnosis of the girl with the diagnosis of facial diplegia. Hypomethylation of ICR1 was confirmed in the RSS patients. Whole exome sequencing (WES) revealed a heterozygous mutation in the PRS patients. WES and array-CGH showed that no relevant variants or copy number variations (CNV) were identified in the CAB patients. Conclusions: On the one hand, newborn children can manifest diverse forms of abnormal craniofacial features, which are usually associated with either major or minor dysmorphic stigmata. A cleft lip/ palate is a major craniofacial malformation, and frontal bossing or a disproportionate craniofacial contour can be falsely considered as a transient plagiocephaly, which is spontaneously resolved by time. On the other hand, many physicians fall into the problem of deeming a countless number of diseases, such as contractures, as an idiopathic or non-specific syndrome. The latter stems from limited clinical experience. Therefore, failing to establish between the onset of the deformity and other inexplicit abnormal features that the patient or their immediate families or relatives carry is the final outcome. In this study, we used, for the first time, a reconstruction CT scan to further delineate the congenital disruption of the craniofacial anatomy and the other skeletal malformation complex.

Simultaneous PSI-Based Orthognathic and PEEK Bone Augmentation Surgery Leads to Improved Symmetric Facial Appearance in Craniofacial Malformations.

(1) The aim of the present study was to compare the outcome of facial symmetry after simultaneous digitally planned patient-specific implant (PSI-) based orthognathic surgery and polyether ether ketone (PEEK) bone augmentation in patients with craniofacial malformations. (2) To evaluate the outcome of the two different surgical approaches (conventional PSI-based orthognathic surgery versus simultaneous PSI-based orthognathic surgery with PEEK bone augmentation), a comparison of five different groups with a combination of the parameters (A) with vs. without laterognathia, (B) syndromic vs. non-syndromic, and (C) surgery with vs. without PEEK bone augmentation was conducted. The digital workflow comprised cone beam CT (CBCT) scans and virtual surgery planning for all patients in order to produce patient specific cutting guides and osteosynthesis plates. Additionally, deformed skulls were superimposed by a non-deformed skull and/or the healthy side was mirrored to produce PSI PEEK implants for augmentation. Retrospective analyses included posterior-anterior conventional radiographs as well as en face photographs taken before and nine months after surgery. (3) Simultaneous orthognathic surgery with PEEK bone augmentation significantly improves facial symmetry compared to conventional orthognathic surgery (6.5%P (3.2-9.8%P) (p = 0.001). (4) PSI-based orthognathic surgery led to improved horizontal bone alignment in all patients. Simultaneous PEEK bone augmentation enhanced facial symmetry even in patients with syndrome-related underdevelopment of both soft and hard tissues.

Relationship between non-syndromic oral clefts and cancer: A systematic review and meta-analysis.

OBJECTIVE: To summarize the clinical evidence on the relationship between cancer and non-syndromic oral cleft (NSOC). METHODS: The review was reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist, and a literature search was conducted in six databases and gray literature. Studies published in any language mentioning cancer in patients with NSOC and their relatives and NSOC in patients with cancer and their relatives were included. Risk of bias was assessed using the Joanna Briggs Institute appraisal tool. The certainty of the evidence was evaluated using the GRADE (Grading of Recommendation, Assessment, Development, and Evaluation) assessment. After a 2-step selection process, 33 studies were included: 17 case-control studies, 13 cross-sectional studies, and 3 case reports. RESULTS: The study evaluated 206,096 patients from 20 countries. Of these, 0.35% of patients with cancer (95% CI: 0.0%-1.1%; I2  = 86%), 3.0% of relatives of patients with cancer (95% CI: 1.19%-5.46%; I2  = 55%), and 0.26% of controls (95% CI: 0.0%-0.83%; I2  = 87%) had NSOC. Among the studies that examined the prevalence of cancer, 2.4% (95% CI: 0.0%-19.3%; I2  = 99%) of patients with NSOC, 15.4% of relatives of patients with NSOC (95% CI: 2.0%-37.6%; I2  = 99%), and 5.3% of controls (95% CI: 0.0%-22.8%; I2  = 99%) had cancer. Although no relationship was observed between the risk of cancer in patients with NSOC and the risk of NSOC in patients with cancer, there was an association for an increased risk of cancer in relatives of patients with NSOC (OR: 9.96, 95% CI: 1.55-63.99; p = 0.01) and a significant association for the NSOC risk in relatives of patients with leukemia (OR: 9.31; 95% CI: 1.13-76.67; p = 0.03). CONCLUSION: Our findings demonstrate an increased risk of cancer in relatives of patients with NSOC and that relatives of patients with leukemia were more frequently affected by NSOC. Together, these findings can help guide cancer screening in patients with NSOC and their relatives and shed light on the risk of NSOC in families with a history of cancer.

Hallermann Streiff syndrome: Cranio-facial manifestations systematic review and report of two cases.

Hallermann Streiff syndrome (HSS) is a rare congenital abnormality with about 200 case reports in the literature. Its etiology is unknown although it may be due to a sporadic mutation. Diagnosis is based on the association of craniofacial malformation, dental abnormalities, hypotrichosis, atrophy of the skin, proportionate nanism, congenital cataract and bilateral microphtalmos. Cranio-facial deformities are the main signs detected and the most easily recognizable. We report cranio-facial and oral signs from a systemic literature review, and illustrate our findings with two of our patients diagnosed with HSS. Common cranio-facial manifestations are craniofacial malformation with a « parrot beak ¼ nose, micrognathia, aprominent skull, sutures closing anomaly, malocclusion, dental anomalies, eyebrows and eyelash lack and atrophy of the nose skin. Knowledge of these signs should allow for early diagnosis and adequate treatment and follow up.

Continuous circular closure in unilateral cleft lip and plate repair in one surgery.

The study aims at assessing wound healing and safety of single-stage two-layers continuous closure in patients with unilateral cleft lip and palate (UCLP). In this retrospective, descriptive cohort study, we assessed wound healing without fistula formation at 1, 3, and 6 months after a single-stage two-layer UCLP repair, in which the midline suture is continuously circular all along the oral and nasal sides. We examined lengths of hospital stay and the incidence of intra- and postoperative adverse events. Furthermore, we compared the cleft width at birth and on the day of surgery, after presurgical orthopaedics. Eleven UCLP patients underwent one cleft surgery between July 2016 and June 2018 at the age of 8-9 months. Full primary healing occurred in all patients without fistulas. Median length of post-operative hospital stay was 5 days (range = 4-9 days). No intra- or postoperative adverse events above Grade I (according to ClassIntra and Clavien-Dindo, respectively) occurred. Median and interquartile range (IQR) of the palatal cleft width decreased significantly from birth to surgery, i.e., from 12.0 mm (10.8-13.6 mm) to 5.0 mm (4.0-7.5 mm) anteriorly and from 14.0 mm (11.5-15.0 mm) to 7.3 mm (6.0-8.5 mm) posteriorly (p = 0.0033 in both cases). Given these preliminary results, the concept of single-stage continuous circular closure in UCLP has potential for further investigation. However, it remains to be proven that there are no relevant adverse effects such as inhibition of maxillary growth. Registered in clinicaltrials.gov:NCT04108416.

Hemifacial microsomia: treatment alternatives-a systematic review of literature.

OBJECTIVE: To systematically review literature on therapeutic options for treating hemifacial microsomia (HFM), in young patients with growth potential, classifying and comparing the different dentofacial treatment methods. STUDY DESIGN: An independent review of databases (Scopus, Embase, Ovid, Cochrane Library and PubMed) following the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA), conducted by four evaluators. The protocol of this study was registered in International prospective register of systematic reviews (PROSPERO), under the number CRD42021293076. RESULTS: Between 1970-2021, a total number of 1137 articles were published of which 27 were included in this study according to the selection criteria: one randomized multicentric trial, two case-control studies, three case series and 21 case reports. CONCLUSIONS: The most common orthopedic treatments provide vertical stimulation of the maxillary process in the affected side. Orthodontic approaches are mainly applied for vertical correction and stabilization of the occlusal plane. Other treatment options include orthognathic surgery, osteogenic distraction, temporomandibular reconstruction and grafting. It is recommended that prospective clinical randomized controlled studies be conducted using homogeneous pediatric groups with long-term follow-up, to establish recommended evidence-based methods for treating each set of hemifacial microsomia symptoms.

Research progress on the regulation of craniofacial development and malformation by fibroblast growth factor 8 / 口腔疾病防治

@#Fibroblast growth factor 8 (FGF8) is a kind of secretory polypeptide that has crucial roles in the development of various tissues and organs. Current studies have found that FGF8 can regulate the differentiation of cranial neural crest cells by activating the mitogen-activated protein kinase (MAPK) signaling pathway and affect the establishment of mandibular arch polarity and the development of craniofacial symmetry by regulating the expression of target genes. Cleft lip with or without cleft palate, ciliopathies, macrostomia and agnathia are four developmental malformations involving the craniofacial region that seriously affect the quality of life of patients. The abnormal FGF8 signal caused by gene mutation, abnormal protein conformation or expression is closely related to the occurrence of craniofacial malformations, but the molecular mechanism and signaling pathway underlying these malformations have not been fully elucidated. Craniofacial development is a complex process mediated by a variety of signaling molecules. In the future, the role of various signaling molecules in craniofacial development and malformations need to be explored to provide a new perspective and vision for the prevention and treatment of these craniofacial malformations.

Genetics of craniofacial malformations.

The field of craniofacial malformations is comprehensive and does not allow to discuss all craniofacial malformations which have been described as single entities. Many of the syndromes with craniofacial malformations are ultrarare. In this review we have chosen craniofacial malformation syndromes which are of relevance for the pediatrician, especially neonatologist: different types of craniosynostoses, oculo-auriculo-vertebral spectrum, Pierre Robin sequence and Treacher Collins syndrome. These syndromes will be described in detail. Diagnostic and therapeutic options will be discussed.

Prenatal Diagnosis of Acromelic Frontonasal Dysostosis.

Acromelic frontonasal dysostosis (AFND; MIM #603671) is a rare autosomal dominant genetic disorder caused by a heterozygous mutation in the ZSWIM6 (KIAA1577) gene located at chromosome 5q12.1. It is phenotypically characterized by frontonasal malformation with hypertelorism, telecanthus, nasal clefting or bifid nasal tip, wide fontanels and sutures, brachycephaly, and cleft palate. The patients also present with central nervous system malformations such as encephalocele, agenesis of the corpus callosum, or interhemispheric lipoma. Limb malformations can also be found, including preaxial polydactyly of the feet and sometimes postaxial polydactyly of the hands, talipes equinovarus, or tibia malformations. Here, we present a case of early prenatal diagnosis of AFND with ultrasound and necropsy images which show the phenotypic findings of this syndrome.

Clinical application of chromosomal microarray analysis for fetuses with craniofacial malformations.

BACKGROUND: The potential correlations between chromosomal abnormalities and craniofacial malformations (CFMs) remain a challenge in prenatal diagnosis. This study aimed to evaluate 118 fetuses with CFMs by applying chromosomal microarray analysis (CMA) and G-banded chromosome analysis. RESULTS: Of the 118 cases in this study, 39.8% were isolated CFMs (47/118) whereas 60.2% were non-isolated CFMs (71/118). The detection rate of chromosomal abnormalities in non-isolated CFM fetuses was significantly higher than that in isolated CFM fetuses (26/71 vs. 7/47, p = 0.01). Compared to the 16 fetuses (16/104; 15.4%) with pathogenic chromosomal abnormalities detected by karyotype analysis, CMA identified a total of 33 fetuses (33/118; 28.0%) with clinically significant findings. These 33 fetuses included cases with aneuploidy abnormalities (14/118; 11.9%), microdeletion/microduplication syndromes (9/118; 7.6%), and other pathogenic copy number variations (CNVs) only (10/118; 8.5%).We further explored the CNV/phenotype correlation and found a series of clear or suspected dosage-sensitive CFM genes including TBX1, MAPK1, PCYT1A, DLG1, LHX1, SHH, SF3B4, FOXC1, ZIC2, CREBBP, SNRPB, and CSNK2A1. CONCLUSION: These findings enrich our understanding of the potential causative CNVs and genes in CFMs. Identification of the genetic basis of CFMs contributes to our understanding of their pathogenesis and allows detailed genetic counselling.

Identification of a novel gross deletion of TCOF1 in a Chinese prenatal case with Treacher Collins syndrome.

BACKGROUND: Treacher Collins syndrome (TCS) is the most common mandibulofacial dysostosis with an autosomal dominant or rarely recessive manner of inheritance. It is still challenging to make a definite diagnosis for affected fetuses with TCS only depending on the ultrasound screening. Genetic tests can contribute to the accurate diagnosis for those prenatal cases. METHODS: Targeted exome sequencing was performed in a fetus of a Chinese family, who presenting an abnormal facial appearance by prenatal 2D and 3D ultrasound screening, including micrognathia, nasal bridge pit, and abnormal auricle. The result was validated with multiplex ligation-dependent probe amplification (MLPA) and real-time quantitative PCR (qPCR). RESULTS: A novel 2-6 exons deletion of TCOF1 gene was identified and confirmed by the MLPA and qPCR in the fetus, which was inherited from the affected father with similar facial anomalies. CONCLUSION: The heterozygous deletion of 2-6 exons in TCOF1 results in the TCS of this Chinese family. Our findings not only enlarge the spectrum of mutations in TCOF1 gene, but also highlight the values of combination of ultrasound and genetics tests in diagnosis of craniofacial malformation-related diseases during perinatal period.

Spliceosomopathies and neurocristopathies: Two sides of the same coin?

Mutations in core components of the spliceosome are responsible for a group of syndromes collectively known as spliceosomopathies. Patients exhibit microcephaly, micrognathia, malar hypoplasia, external ear anomalies, eye anomalies, psychomotor delay, intellectual disability, limb, and heart defects. Craniofacial malformations in these patients are predominantly found in neural crest cells-derived structures of the face and head. Mutations in eight genes SNRPB, RNU4ATAC, SF3B4, PUF60, EFTUD2, TXNL4, EIF4A3, and CWC27 are associated with craniofacial spliceosomopathies. In this review, we provide a brief description of the normal development of the head and the face and an overview of mutations identified in genes associated with craniofacial spliceosomopathies. We also describe a model to explain how and when these mutations are most likely to impact neural crest cells. We speculate that mutations in a subset of core splicing factors lead to disrupted splicing in neural crest cells because these cells have increased sensitivity to inefficient splicing. Hence, disruption in splicing likely activates a cellular stress response that includes increased skipping of regulatory exons in genes such as MDM2 and MDM4, key regulators of P53. This would result in P53-associated death of neural crest cells and consequently craniofacial malformations associated with spliceosomopathies.

Correlation between Type of Clefting and the Incidence of Otitis Media among Children with Lip and/or Palate Clefts.

INTRODUCTION: Otitis media is a frequent condition among children with high morbidity. Orofacial clefts are undoubtedly one of the most well-established risk factors for otitis media during childhood. The clinical spectrum of disease in orofacial clefting is broad according to the subtype of malformation. This study aims to correlate the occurrence of otitis media among lip and/or palate cleft children with clinical and epidemiological parameters, in particular with the subtypes of malformation diagnosed. METHODS: This is a clinical, retrospective, case-control type of study. Epidemiological and clinical data were obtained from medical records of children born between 2005 and 2008 and attending a multidisciplinary center for cleft patients. RESULTS: 53% of the patients had registers of middle ear disorder during follow-up, and secretory otitis media was the most frequently diagnosed condition. Five children (1.39%) had chronic otitis media during the study period. Those patients with malformations including involvement of structures located posteriorly to the incisive foramen were more frequently diagnosed with otitis media than those with isolated pre-foramen cleft (p value < 0.001, odds ratio: 5.33). Gender and bilateral malformations did not correlate with increased occurrence of middle ear disease (p value > 0.05). CONCLUSION: Otitis media is frequent among lip and/or palate cleft children, although the grade of middle ear involvement seems to vary widely within this population. Post-foraminal malformations are clearly associated with increased incidence of otitis media, as well as with more severe diseases.