Limb reduction in an Esco2 cohesinopathy mouse model is mediated by p53-dependent apoptosis and vascular disruption.

Roberts syndrome (RBS) is an autosomal recessive disorder with profound growth deficiency and limb reduction caused by ESCO2 loss-of-function variants. Here, we elucidate the pathogenesis of limb reduction in an Esco2fl/fl;Prrx1-CreTg/0 mouse model using bulk- and single-cell-RNA-seq and gene co-expression network analyses during embryogenesis. Our results reveal morphological and vascular defects culminating in hemorrhage of mutant limbs at E12.5. Underlying this abnormal developmental progression is a pre-apoptotic, mesenchymal cell population specific to mutant limb buds enriched for p53-related signaling beginning at E9.5. We then characterize these p53-related processes of cell cycle arrest, DNA damage, cell death, and the inflammatory leukotriene signaling pathway in vivo. In utero treatment with pifithrin-α, a p53 inhibitor, rescued the hemorrhage in mutant limbs. Lastly, significant enrichments were identified among genes associated with RBS, thalidomide embryopathy, and other genetic limb reduction disorders, suggesting a common vascular etiology among these conditions.

Surgical Correction of Orbital Hypertelorism With Absorbable Plate Instead of Frontal and Orbital Bar and Inverted U-Shaped Osteotomy.

OBJECTIVE: The aim of the study is to investigate the effect and feasibility of using absorbable plate instead of frontal and orbital bar and inverted U-shaped osteotomy to correct the widening of orbital distance. METHODS: The surgical effect and feasibility of using absorbable plate instead of frontal and orbital bridge plus inverted U-osteotomy for orbital widening syndrome in seven cases between January 2019 and February 2022 were retrospectively analyzed. First, the surgical procedure for orbital hypertelorism was inverted U-shaped orbital osteotomy, and a frontal bone flap was removed, exposing the superior orbital margin and the orbital circumference, and the orbital bone was directly cut off by inverted U-shaped osteotomy. The widened bone in the middle of the orbit was removed, and a long absorbable plate was used to replace the orbitofrontal bridge. The two sides of the orbit were fixed on the absorbable plate, and the absorbable plate was fixed on the rear skull. The clinical effect of treatment, complications (such as cerebrospinal fluid leakage and infection), safety, and feasibility of surgery were evaluated. RESULTS: Using absorbable plate instead of fronto-orbital bridge achieved the effect of orbitofrontal bridge, without orbital distance widening, cerebrospinal fluid leakage, and intracranial infection. Operating time was reduced. There was no metal fixation, and there was no risk of a second operation. CONCLUSIONS: The effect of replacing the frontal-orbital bridge with an absorbable plate and inverted U-shaped osteotomy is positive, the operation time is short, and the orbital distance is clearly improved. This approach can replace the traditional orbital-distance operation, and the incidence of postoperative cerebrospinal fluid leakage and infection is low. Long-term follow-up results are stable.

Truncating variants of the sterol recognition region of SHH cause hypertelorism phenotype rather than hypotelorism-holoprosencephaly.

Sonic hedgehog signaling molecule (SHH) is a key molecule in the cilia-mediated signaling pathway and a critical morphogen in embryogenesis. The association between loss-of-function variants of SHH and holoprosencephaly is well established. In mice experiments, reduced or increased signaling of SHH have been shown to be associated with narrowing or excessive expansion of the facial midline, respectively. Herein, we report two unrelated patients with de novo truncating variants of SHH presenting with hypertelorism rather than hypotelorism. The first patient was a 13-year-old girl. Her facial features included hypertelorism, strabismus, telecanthus, malocclusion, frontal bossing, and wide widow's peak. She had borderline developmental delay and agenesis of the corpus callosum. She had a nonsense variant of SHH: Chr7(GRCh38):g.155802987C > T, NM_000193.4:c.1302G > A, p.(Trp434*). The second patient was a 25-year-old girl. Her facial features included hypertelorism and wide widow's peak. She had developmental delay and agenesis of the corpus callosum. She had a frameshift variant of SHH: Chr7(GRCh38):g.155803072_155803074delCGGinsT, NM_000193.4:c.1215_1217delCCGinsA, p.(Asp405Glufs*92). The hypertelorism phenotype contrasts sharply with the prototypical hypotelorism-holoprosencephaly phenotype associated with loss-of-function of SHH. We concluded that a subset of truncating variants of SHH could be associated with hypertelorism rather than hypotelorism.

[Analysis of genetic etiology in a patient with 1p36 deletion syndrome in conjunct with Snijders Blok-Campeau syndrome].

OBJECTIVE: To explore the genetic basis for a patient with unexplained developmental delay and special facial features. METHODS: A male patient admitted to the Maternal and Child Health Care Hospital of Gansu Province on May 27, 2021 due to infertility was selected as the study subject. Clinical data of the patient was collected, and genomic DNA was extracted from peripheral blood samples from the patient and his parents. Whole exome sequencing (WES) was carried out, and candidate variant was verified by Sanger sequencing. RESULTS: The patient was found to harbor a 2.54 Mb deletion in 1p36.33p36.32 and a heterozygous c.1123G>C (p.E375Q) variant of the CHD3 gene, neither of which was detected in his parents. CONCLUSION: The patient was diagnosed with Snijders Blok-Campeau syndrome in conjunct with 1p36 deletion syndrome, which has enabled genetic counseling for his family.

Human diprosopus: Case report of a rare congenital abnormality.

Diprosopus is a congenital anomaly in which partial or complete duplication of craniofacial structures occurs. Because it is rare, the mortality rate is high, and information concerning this anomaly is scarce. This study describes a case of human diprosopus in a 9-year-old male individual, who has severe complications associated with the central nervous, cardiovascular, respiratory, and digestive systems. Since birth, he has been monitored in a specialized hospital environment, where he has undergone several surgeries and multidisciplinary treatments. Regarding the craniofacial aspects, he had agenesis of the corpus callosum, floor of the nasal cavity, and floor of the anterior cranial fossa, in addition to the presence of bone dysplasia, ocular hypertelorism and cleft palate with nasal and oral teratoma. Regarding dental characteristics, the patient has duplication of the maxilla, mandible, tongue, and some teeth. After complementary imaging exams, several supernumerary teeth were found, with some being impacted and in complex regions, with an indication for extraction due to the risks of impaction, irruptive deviation, root resorption, and associated cystic or tumoral lesions. Because of the numerous complications, knowledge, and preparation of the entire team is necessary for the correct management of the case.

Absence of the RING domain in MID1 results in patterning defects in the developing human brain.

The X-linked form of Opitz BBB/G syndrome (OS) is a monogenic disorder in which symptoms are established early during embryonic development. OS is caused by pathogenic variants in the X-linked gene MID1 Disease-associated variants are distributed across the entire gene locus, except for the N-terminal really interesting new gene (RING) domain that encompasses the E3 ubiquitin ligase activity. By using genome-edited human induced pluripotent stem cell lines, we here show that absence of isoforms containing the RING domain of MID1 causes severe patterning defects in human brain organoids. We observed a prominent neurogenic deficit with a reduction in neural tissue and a concomitant increase in choroid plexus-like structures. Transcriptome analyses revealed a deregulation of patterning pathways very early on, even preceding neural induction. Notably, the observed phenotypes starkly contrast with those observed in MID1 full-knockout organoids, indicating the presence of a distinct mechanism that underlies the patterning defects. The severity and early onset of these phenotypes could potentially account for the absence of patients carrying pathogenic variants in exon 1 of the MID1 gene coding for the N-terminal RING domain.

A Japanese patient with Teebi hypertelorism syndrome and a novel CDH11 EC1 domain variant.

The gene CDH11 encodes cadherin-11, a Type II cadherin superfamily member that contains five extracellular cadherin (EC) domains. Cadherin-11 undergoes trans-dimerization via the EC1 domain to generate cadherin complexes. Compound heterozygous and homozygous loss-of-function CDH11 variants are observed in Elsahy-Waters syndrome (EWS), which shows characteristic craniofacial features, vertebral abnormalities, cutaneous syndactyly in 2-3 digits, genitourinary anomalies, and intellectual disability. Heterozygous CDH11 variants can cause Teebi hypertelorism syndrome (THS), which features widely spaced eyes and hypospadias. We report a THS patient with a novel CDH11 variant involving the EC1 domain. The patient was a 10-month-old male with normal developmental milestones, but had widely spaced eyes, strabismus, hypospadias, shawl scrotum, broad thumbs (right bifid thumb in x-ray), polysyndactyly of the left fourth finger, and cutaneous syndactyly of left third/fourth fingers. Exome sequencing identified a de novo heterozygous CDH11 variant (NM_001797.4:c.229C > T [p.Leu77Phe] NC_000016.9:g.64998856G > A). Clinical features were consistent with previously reported THS patients, but polysyndactyly, broad thumb, and cutaneous syndactyly overlapped phenotypic features of EWS. THS and EWS may represent a spectrum of CDH11-related disorders. Residue Leu77 in this novel CDH11 variant lines a large hydrophobic pocket where side chains of the partner cadherin-11 insert to trans-dimerize, suggesting that the cadherin-11 structure might be altered in this variant.

Multiple rhabdomyomatous mesenchymal hamartomas in a patient with mosaic Barber-Say syndrome.

Barber-Say syndrome (BSS) is a rare congenital ectodermal dysplasia with few cases reported in the literature. We describe a 9-year-old boy with congenital generalized hypertrichosis and multiple rhabdomyomatous mesenchymal hamartomas (RMHs) on his nose and periocular region. Next-generation sequencing, performed in DNA from a blood sample, and RMH tissue, revealed a pathogenic variant in the TWIST2 gene, which was not detected in a salivary sample of the patient, nor in his parents. Therefore, we consider this variant as de novo mosaicism. To our knowledge, this is the first case of multiple RMHs associated with BSS.

A severe neurocognitive phenotype caused by biallelic CHD3 variants in two siblings.

CHD3 heterozygous variants are associated with Snijders Blok-Campeau syndrome (SBCS) which consists of intellectual disability (ID), macrocephaly, and dysmorphic facies. Most reported variants are missense or loss of function clustered within the ATPase/helicase domain of the protein. We report a severe neurocognitive phenotype caused by biallelic CHD3 variants in two siblings, each inherited from a mildly affected parent. Male and female siblings were referred to the Genetics Clinic due to severe ID and profound dysmorphism. The parents are first cousins of Iranian descent with borderline intellectual abilities. Exome sequencing was performed for the affected female and her parents. A single homozygous candidate variant in the CHD3 gene was detected in the proband: c.5384_5389dup. p.Arg1796_Phe1797insTrpArg, resulting in an in-frame insertion of 2 amino acids located outside the ATPase/helicase domain at the C-terminal region of CHD3-encoding residues. This variant is classified as likely pathogenic according to ACMG guidelines. The variant was detected in a heterozygous state in each parent. Both affected siblings were homozygous, while their unaffected brother did not carry the variant. Biallelic CHD3 variants cause a severe neurodevelopmental syndrome that is distinguishable from SBCS. We assume that the variant type (in-frame insertion) and location may enable CHD3 biallelic variants.

A novel SMOC1 pathogenic homozygous variant in a fetus with mesomelia of the lower limbs, micrognathia and hypertelorism and an incidental finding of CYP21A2-related congenital adrenal hyperplasia.

Trio exome sequencing was performed on a fetus with bilateral mesomelia of the lower limbs with significant angulation of the tibial bones, micrognathia and hypertelorism detected on ultrasound scan at 19 + 0 weeks gestation. The couple is consanguineous. A homozygous pathogenic frameshift variant in the SMOC1 gene (c.339_340del p.(Phe114Cysfs*40)) was detected and both parents were shown to be heterozygous. Pathogenic variants in the SMOC1 gene are associated with microphthalmia with limb anomalies which multidisciplinary team discussion determined to be causal of the scan anomalies detected. The fetus was also a compound heterozygote for CYP21A2 pathogenic variants, confirming a second diagnosis of non-classical congenital adrenal hyperplasia, which was felt incidental to the scan findings. The risk that this couple's next pregnancy would be affected by either of these disorders is 1 in 4 (25%) and demonstrates the importance of genetic diagnoses for the family and implications for future pregnancies.

Flexible Actuators with Hygroscopic Adaptability for Smart Wearables and Soft Grippers.

Flexible actuators have garnered significant interest in the domains of biomedical devices, human-machine interfaces, and smart wearables. However, the mechanical properties of existing materials are not sufficiently robust, and the expensive and time-consuming pretreatment process and the ambiguous high-degree-of-freedom deformation mechanism make it difficult to meet the demands of industrialized production. Hence, drawing inspiration from the adaptable movement of living organisms in the natural world, this research created and engineered a fully textile-based humidity-sensitive flexible actuator (TbHs-FA) using high-cost-effective viscose/PET fibers as raw materials. The breakthrough development in actuation performance is covered, including substantial contraction force (92.53 cN), high actuation curvature (16.78 cm-1), and fast response (264 cN s-1 and 46.61 cm-1 s-1). Additionally, the programmable stiffness system and weave structure give TbHs-FAs low hysteresis and fatigue resistance, narrowing the gap between the conceptual laboratory-scale design of existing fully textile-based humidity-sensitive flexible actuators and actual textiles. The high-degree-of-freedom and large bending deformation mechanisms are elucidated for the first time by combining microscopic mechanical structure simulation and macroscopic energy conversion analysis. The novel humidity-sensitive flexible actuator possesses strong mechanical qualities, making it suitable for applications such as flexible robots, medicinal devices, and smart wearables.

Snijders Blok-Campeau Syndrome: Description of 20 Additional Individuals with Variants in CHD3 and Literature Review.

Snijders Blok-Campeau syndrome (SNIBCPS, OMIM# 618205) is an extremely infrequent disease with only approximately 60 cases reported so far. SNIBCPS belongs to the group of neurodevelopmental disorders (NDDs). Clinical features of patients with SNIBCPS include global developmental delay, intellectual disability, speech and language difficulties and behavioral disorders like autism spectrum disorder. In addition, patients with SNIBCPS exhibit typical dysmorphic features including macrocephaly, hypertelorism, sparse eyebrows, broad forehead, prominent nose and pointed chin. The severity of the neurological effects as well as the presence of other features is variable among subjects. SNIBCPS is caused likely by pathogenic and pathogenic variants in CHD3 (Chromodomain Helicase DNA Binding Protein 3), which seems to be involved in chromatin remodeling by deacetylating histones. Here, we report 20 additional patients with clinical features compatible with SNIBCPS from 17 unrelated families with confirmed likely pathogenic/pathogenic variants in CHD3. Patients were analyzed by whole exome sequencing and segregation studies were performed by Sanger sequencing. Patients in this study showed different pathogenic variants affecting several functional domains of the protein. Additionally, none of the variants described here were reported in control population databases, and most computational predictors suggest that they are deleterious. The most common clinical features of the whole cohort of patients are global developmental delay (98%) and speech disorder/delay (92%). Other frequent features (51-74%) include intellectual disability, hypotonia, hypertelorism, abnormality of vision, macrocephaly and prominent forehead, among others. This study expands the number of individuals with confirmed SNIBCPS due to pathogenic or likely pathogenic variants in CHD3. Furthermore, we add evidence of the importance of the application of massive parallel sequencing for NDD patients for whom the clinical diagnosis might be challenging and where deep phenotyping is extremely useful to accurately manage and follow up the patients.

Opitz GBBB syndrome with total anomalous pulmonary venous connection: A new MID1 gene variant.

BACKGROUND: Opitz GBBB syndrome (GBBB) is an X-linked disease characterized by midline defects, including congenital heart defects. We present our diagnostic approach to the identification of GBBB in a consanguineous family in which two males siblings were concordant for a total anomalous connection of pulmonary veins and minor facial dysmorphias. METHODS: Targeted exome sequencing analysis of a 380-gene panel associated with cardiovascular disease was performed on the propositus. Interpretative analysis of the exome results was conducted, and 3D models of the protein changes were generated. RESULTS: We identified a NM_000381.4:c.608G>A;p.(Arg203Gln) change in MID1, affecting the conformation of the B-box 2 domain of the protein, with a zinc finger structure and associated protein interactions. This clinical phenotype is consistent with GBBB; however, the type of congenital heart disease observed in this case has not been previously reported. CONCLUSION: A new likely pathogenic variant on MID1 c.608G>A was found to be associated with Opitz GBBB syndrome.

Surgical management of penoscrotal hypospadias in a child with Opitz G/BBB syndrome: a case report.

Opitz G/BBB syndrome is a rare condition characterized by three significant anomalies; hypertelorism, cleft lip and palate, and hypospadias. However, other anomalies may be associated. Herein, we report a 4-year-old child presented with penoscrotal hypospadias. On examination, hypertelorism and cleft lip and palate were noticed, suggesting a diagnosis of Opitz G/BBB syndrome. The cleft lip was corrected in the first year, and a two-staged surgical approach was implemented for penoscrotal hypospadias. In the first stage, the chordee was corrected and urethral plate was reconstructed using a tabularized incised plate urethroplasty and testicular tunica vaginalis flap. In the second stage, the remanent hypospadias was corrected, and the meatal opening reached its normal location. In conclusion, a two-staged surgical approach for the treatment of penoscrotal hypospadias associated with Opitz G/BBB syndrome may provide excellent outcomes in early-recognized cases. The urologist should pay attention to abnormal facial characteristics in patients with hypospadias.

Comparison of Piezosurgery and Conventional Osteotomy for Orbital Hypertelorism Surgical Correction.

The purpose of this study was to compare the safety and effect of piezosurgery with conventional osteotomy in a box-shifting procedure for orbital hypertelorism (ORH) correction surgery. This study retrospectively analyzed the clinical record of 10 ORH patients aged from 5 to 12 years, and they were second-degree ORH with an interorbital distance (IOD) of 35 to 37.8 mm. Three of them received the osteotomy with piezosurgery (the piezosurgery group), whereas the other 7 patients received osteotomy with the conventional osteotomy method (the control group). They were compared with age and preoperative IOD. All the patients' IOD was effectively improved to normal range after the surgery. The results showed that the application of piezosurgery did not prolong the surgery time (piezosurgery group: 8.3±0.5 hours; control group: 8.7±1.4 hours, P =0.68). Furthermore, the patients in the piezosurgery group had less drainage volume (piezosurgery group: 79.1±12 mL; the control group: 170±41.3 mL, P =0.0065) and shorter postoperative hospital stay (piezosurgery group: 8.3±2.0 d; control group: 12.43±2.29 d, P =0.029). There were 2 patients who had wound infections, 1 in the piezosurgery group and 1 in the control group, respectively. However, 1 patient in the control group suffered from cerebrospinal fluid leakage. On the basis of the results, the application of piezosurgery benefited the patients on a better and smoother recovery course with less drainage and shorter hospital stays. The advantages of piezosurgery are the fine and precise osteotomy and the protection for soft tissue, which make it a comparatively safe and effective tool for craniofacial surgery, especially for young patients.

Augmentation of bone morphogenetic protein signaling in cranial neural crest cells in mice deforms skull base due to premature fusion of intersphenoidal synchondrosis.

Craniofacial anomalies (CFAs) are a diverse group of disorders affecting the shapes of the face and the head. Malformation of the cranial base in humans leads CFAs, such as midfacial hypoplasia and craniosynostosis. These patients have significant burdens associated with breathing, speaking, and chewing. Invasive surgical intervention is the current primary option to correct these structural deficiencies. Understanding molecular cellular mechanism for craniofacial development would provide novel therapeutic options for CFAs. In this study, we found that enhanced bone morphogenetic protein (BMP) signaling in cranial neural crest cells (NCCs) (P0-Cre;caBmpr1a mice) causes premature fusion of intersphenoid synchondrosis (ISS) resulting in leading to short snouts and hypertelorism. Histological analyses revealed reduction of proliferation and higher cell death in ISS at postnatal day 3. We demonstrated to prevent the premature fusion of ISS in P0-Cre;caBmpr1a mice by injecting a p53 inhibitor Pifithrin-α to the pregnant mother from E15.5 to E18.5, resulting in rescue from short snouts and hypertelorism. We further demonstrated to prevent premature fusion of cranial sutures in P0-Cre;caBmpr1a mice by injecting Pifithrin-α through E8.5 to E18.5. These results suggested that enhanced BMP-p53-induced cell death in cranial NCCs causes premature fusion of ISS and sutures in time-dependent manner.

Surgical Management of Hypertelorism: The 3D Animated Technical Note.

The hypertelorism surgery is a complex procedure requiring a long learning curve. Even though the box osteotomy technique is well described in literature, its representation is generally based on texts and illustrations that do not really give a 3-dimensional or a dynamic point of views. The authors present a 3-dimensional animated video, Supplemental Digital Content 1, http://links.lww.com/SCS/E561 showing the craniofacial osteotomies and focusing on the critical points to correct hypertelorism.

Reconstructive Operation of Severe Orbital Hypertelorism With Computer-Assisted Precise Virtual Plan.

Orbital hypertelorism correction is still a less precise procedure, with a simple preoperative design and surgical results often depending on the operator's experience. In recent years, computer-assisted technology has been fully utilized in craniofacial surgery. This article aims to explore the clinical results of computer-assisted technology in orbital hypertelorism correction and discuss its advantages and effects on treatment. Four patients with orbital hypertelorism underwent intracranial and extracranial combined box osteotomy correction. Preoperative computed tomography scans were performed, and 3-dimensional 3D digital technology was used to measure the orbital spacing, virtually design the 3D cutting scheme, and guide the intraoperative 3D cutting to improve the accuracy of periorbital osteotomy and reduce the surgical risk. Four patients underwent successful surgery, and the average distance of the medial orbital wall was decreased from 43.6 to 23.4 mm. Computer-assisted box osteotomy shortens the operative time and provides better corrective results.