Helsmoortel-Van der Aa syndrome in a 13-year-old girl with autistic spectrum disorder, dysmorphism, a right solitary kidney, and polycystic ovaries: a case report.

BACKGROUND: Helsmoortel-Van der Aa syndrome was officially documented in 2014. Helsmoortel-Van der Aa syndrome is an extremely rare complex neurodegenerative disorder characterized by reduced intellectual capacity, motor dysfunction, facial dysmorphism, impaired development, and an increased predisposition to autism spectrum disorder. In addition, many patients also present with neuropsychiatric disorders, including attention deficit hyperactivity disorder, anxiety disorders, and various behavioral abnormalities. Helsmoortel-Van der Aa syndrome is challenging to identify solely on the basis of symptoms, and genetic investigations, including exome sequencing, may facilitate diagnosis. CASE PRESENTATION: We report a case of 13-year-old Saudi patient who presented with dysmorphic features as illustrated in Fig. 1, severe mental retardation, autism spectrum disorder, and attention deficit hyperactivity disorder. Initial genetic testing was unremarkable; thus, a clinical exome analysis was performed to identify the genetic basis of the condition. CONCLUSIONS: Clinical exome analysis indicated an autosomal dominant Helsmoortel-Van der Aa syndrome with a likely pathogenic de novo variant within the activity-dependent neuroprotector homeobox (ADNP) gene not previously reported in Helsmoortel-Van der Aa syndrome. The patient had a right-sided solitary kidney and polycystic ovaries, conditions that were not previously associated with HVDAS.

Sanjad-Sakati Syndrome Revealed by Hypocalcemic Convulsions.

Sanjad-Sakati syndrome is an autosomal recessive disorder characterized by facial dysmorphia, growth retardation, and congenital hypoparathyroidism. Epidemiologically, this syndrome is primarily observed in children of Arabian descent. However, cases have also been reported in non-Arab countries. Although its exact prevalence is uncertain, the estimated incidence in Saudi Arabia ranges from one in 40,000 to one in 600,000 live births. We report a case of Sanjad-Sakati syndrome in a female infant, born to first-degree consanguineous parents, who presented with convulsive seizures since the age of four months. Laboratory findings indicated severe hypocalcemia and elevated phosphate levels, consistent with congenital hypoparathyroidism. The treatment involved calcium and vitamin D supplementation, which led to a marked improvement in the patient's condition. The objective of this clinical case is to highlight an uncommon cause of hypocalcemia and to describe certain clinical and endocrinological manifestations of Sanjad-Sakati syndrome, which is prevalent in the Arab population.

Allogeneic Hematopoietic Stem Cell Transplantation in Immunodeficiency-Centromeric Instability-Facial Dysmorphism (ICF) Syndrome: an EBMT/ESID Inborn Errors Working Party Study.

Immunodeficiency-Centromeric instability-Facial dysmorphism (ICF) syndrome is an inborn error of immunity characterized by progressive immune dysfunction and multi-organ disease usually treated with antimicrobial prophylaxis and immunoglobulin substitution. Allogeneic hematopoietic stem cell transplantation (HSCT) is the only curative treatment, but data on outcome are scarce. We provide a detailed description of disease characteristics and HSCT outcome in an international cohort of ICF syndrome patients. Eighteen patients (including all four genotypes) were enrolled. Main HSCT indications were infections (83%), enteropathy/failure to thrive (56%), immune dysregulation (22%) and myelodysplasia/haematological malignancy (17%). Two patients underwent pre-emptive HSCT after early diagnosis. Patients were transplanted between 2003-2021, at median age 4.3 years (range 0.5-19), after myeloablative or reduced-intensity conditioning, from matched sibling or matched family donors, matched unrelated or mismatched donors in 39%, 50% and 12% of cases respectively. Overall survival was 83% (all deaths occurred within the first 5 months post-HSCT; mean follow-up 54 months (range 1-185)). Acute GvHD occurred in 35% of patients, severe (grade III) in two (12%), while none developed chronic GvHD. At latest follow-up (median 2.2 years (range 0.1-14)), complete donor chimerism was achieved in 15/17 surviving patients. All survivors demonstrated normalized T and B cell numbers. Immunoglobulin substitution independence was achieved in all but two patients. All survivors recovered from pre-transplant infections, enteropathy/failure to thrive and immune dysregulation. All three patients transplanted at young age (≤ 3 years), after early diagnosis, survived. The favourable clinical and immunological HSCT outcome in this cohort of patients supports the timely use of this curative treatment in ICF syndrome.

Homozygous TBCE Gene Mutation c.155-166del in a Libyan Patient with Sanjad-Sakati Syndrome: Same Gene Mutation Responsible in All Arab Ethnic Patients.

Sanjad-Sakati syndrome (SSS) (Online Mendelian Inheritance in Man 241410) is a rare autosomal recessive disorder also known as hypoparathyroidism-retardation-dysmorphism syndrome. It is characterized by congenital hypoparathyroidism, growth retardation, typical facial features, and variable developmental delay. SSS is caused due to mutations of the tubulin-specific chaperone E ( TBCE ) gene. In this article, we reported the first Libyan child of first parental consanguinity with SSS and whole exome sequencing results identified the homozygous missense variant c.155-166del and it encodes p.(Ser52-Gly55del) (chr1:235564867) located in the TBCE gene , chromosome 1q42.3. In addition, the patient was also diagnosed with congenital hypothyroidism and presented with acquired bilateral cataract in the first year of life. Most likely, all Arab patients with SSS syndrome have the same TBCE gene mutation.

Recurrent Skin Ulcers with Facial Dysmorphism and Sinopulmonary Infections: Thinking Beyond Hyper-IgE Syndrome.

Prolidase deficiency (PD) is a rare inborn error of metabolism causing ulcers and other skin disorders, splenomegaly, developmental delay, and recurrent infections. Most of the literature is constituted of isolated case reports. It occurs due to the mutations in the prolidase gene ( PEPD ) that result in loss of prolidase activity. We reported here a child who had presented with features compatible with hyper-immunoglobulin E syndrome (HIES) like recurrent skin ulcers, recurrent infections, facial dysmorphism, retained primary teeth, and elevated levels of immunoglobulin E levels but with normal flow cytometric assays, which was later diagnosed as PD.

Facial dysmorphism and Limb abnormalities of Fetal Valproate Syndrome.

A neonate born to nonconsanguineous parents was evaluated for dysmorphic features. The neonate was born at term by normal vaginal delivery. The mother has had epilepsy for 12 years and has been on sodium valproate (700 mg/day) since conception and throughout pregnancy. Examination revealed facial dysmorphism, including triangular forehead, sparse arched eyebrows, telecanthus, flat nasal bridge, long thin upper vermilion border, smooth philtrum, and low-set ears. The limb anomalies observed were arachnodactyly, wrist and elbow contractures, clinodactyly, hypoplastic toenails, and overlapping toes. The other dysmorphisms noted were widely spaced nipples and hypospadias. Ultrasonogram (USG) cranium showed bilateral choroid plexus cysts, and USG abdomen revealed bilateral mild hydronephrosis. 2D-Echocardiography revealed a small patent ductus arteriosus (PDA). A diagnosis of fetal valproate syndrome (FVS) was considered, and other differentials, including fetal alcohol syndrome and genetic conditions, were ruled out by a clinical geneticist review. The index neonate is currently on multidisciplinary follow-up. The index neonate had common features of FVS as described in the literature, in addition to wrist and elbow contractures. Apart from the anomalies, there is a significant risk for neurocognitive delay and neurodevelopmental disorders. Postnatally, these babies need multidisciplinary care and neurodevelopmental follow-up. Valproate use for treating epilepsy in pregnant women and women of childbearing age may be restricted, and alternative choices of ASMs with better safety profiles should be preferred. Facial dysmorphism and limb anomalies in fetal valproate syndrome may occur irrespective of the dose of sodium valproate. Fetal valproate syndrome may present with wrist and elbow contractures.

Toward 3D facial analysis for recognizing Mendelian causes of autism spectrum disorder.

Recognizing Mendelian causes is crucial in molecular diagnostics and counseling for patients with autism spectrum disorder (ASD). We explored facial dysmorphism and facial asymmetry in relation to genetic causes in ASD patients and studied the potential of objective facial phenotyping in discriminating between Mendelian and multifactorial ASD. In a cohort of 152 ASD patients, 3D facial images were used to calculate three metrics: a computational dysmorphism score, a computational asymmetry score, and an expert dysmorphism score. High scores for each of the three metrics were associated with Mendelian causes of ASD. The computational dysmorphism score showed a significant correlation with the average expert dysmorphism score. However, in some patients, different dysmorphism aspects were captured making the metrics potentially complementary. The computational dysmorphism and asymmetry scores both enhanced the individual expert dysmorphism scores in differentiating Mendelian from non-Mendelian cases. Furthermore, the computational asymmetry score enhanced the average expert opinion in predicting a Mendelian cause. By design, our study does not allow to draw conclusions on the actual point-of-care use of 3D facial analysis. Nevertheless, 3D morphometric analysis is promising for developing clinical dysmorphology applications in diagnostics and training.

Spectrum of Multiple Congenital Anomalies-Hypotonia-Seizures Syndrome 3 (MCAHS3) Due to Phosphatidylinositol Glycan Biosynthesis Class T (PIGT) Gene Mutations: A Narrative Review.

Multiple congenital anomalies-hypotonia-seizures syndrome 3 (MCAHS3) results from mutations in the phosphatidylinositol glycan biosynthesis class T (PIGT) gene leading to defects in glycosylphosphatidylinositol transamidase complex (GPI-TA) synthesis. Glycosylphosphatidylinositol serves as an anchor to more than 150 mammalian proteins for attachment on cell surfaces, enabling specific functional properties. Mutations in the PIGT gene result in disruption of this extremely important post-translational protein modification, yielding dysfunctional proteins leading to MCAHS3. An exhaustive literature search was conducted across various electronic databases to reveal only 41 reported cases of MCAHS3 worldwide, emphasizing the rarity of this condition. Multiple congenital anomalies-hypotonia-seizures syndrome 3 has been reported as secondary to 18 different known PIGT variants to date, manifesting as a varying spectrum of craniofacial dysmorphism, developmental delay with epilepsy, cardiac and renal malformations, and unique features in biochemical testing and neuroimaging. This review aims to highlight the constellation of clinical symptoms, diagnostic modalities, and management challenges associated with MCAHS3 cases. It would help determine optimal diagnostic and treatment strategies for newly identified cases and facilitate new research on this rare condition.

CDON Mutation Related to Nose Deformity with Variable Expression in Holoprosencephaly in an Iranian Family: A Case Report.

Holoprosencephaly, a complicated brain abnormality arising from incomplete prosencephalon cleavage, affects both the forebrain and the face. Holoprosencephaly Type 11, with variable expression or partial penetrance, is caused by CDON pathogenic variants associated with the disrupted Sonic Hedgehog (SHH)-pathway. Herein, we aimed to describe a family with genetic nose problems. After counselling and drawing pedigree in Farhud's Genetic Clinic, Tehran, Iran in 2021, DNA extraction of a proband and a few members of his family (patient and control) was conducted. Whole exome sequencing was utilized for detecting the gene and its variant in the proband with a nose deformity. The results were confirmed with Sanger sequencing. This variant was checked in other members by Sanger sequencing. Analysis of the Exome data showed a heterozygous splicing variant in the CDON gene (NM_016952; c.3276+1G>T) in the proband who had a nose deformity and then the results were confirmed with Sanger sequencing. Such a variant was observed in Proband's brother with a nose deformity and was not observed in Proband's cousin with no abnormal phenotype. Recent investigations, in an Iranian family, with a heterozygous splicing CDON mutation as a human candidate gene are discussed for the first time in relation to the likely pathogenesis of facial deformities, particularly nose deformity, in Holoprosencephaly.

Next-generation phenotyping in Nigerian children with Cornelia de Lange syndrome.

Next-generation phenotyping (NGP) can be used to compute the similarity of dysmorphic patients to known syndromic diseases. So far, the technology has been evaluated in variant prioritization and classification, providing evidence for pathogenicity if the phenotype matched with other patients with a confirmed molecular diagnosis. In a Nigerian cohort of individuals with facial dysmorphism, we used the NGP tool GestaltMatcher to screen portraits prior to genetic testing and subjected individuals with high similarity scores to exome sequencing (ES). Here, we report on two individuals with global developmental delay, pulmonary artery stenosis, and genital and limb malformations for whom GestaltMatcher yielded Cornelia de Lange syndrome (CdLS) as the top hit. ES revealed a known pathogenic nonsense variant, NM_133433.4: c.598C>T; p.(Gln200*), as well as a novel frameshift variant c.7948dup; p.(Ile2650Asnfs*11) in NIPBL. Our results suggest that NGP can be used as a screening tool and thresholds could be defined for achieving high diagnostic yields in ES. Training the artificial intelligence (AI) with additional cases of the same ethnicity might further increase the positive predictive value of GestaltMatcher.

Craniofacial dysmorphism of osteogenesis imperfecta mouse and effect of cathepsin K knockout: Preliminary craniometry observations.

OBJECTIVES: In addition to bone fragility, patients with osteogenesis imperfecta (OI) type III have typical craniofacial abnormalities, such as a triangular face and maxillary micrognathism. However, in the osteogenesis imperfecta mouse (oim), a validated model of OI type III, few descriptions exist of craniofacial phenotype. Treatment of OI mostly consists of bisphosphonate administration. Cathepsin K inhibition has been tested as a promising therapeutic approach for osteoporosis and positive results were observed in long bones of cathepsin K knocked out oim (oim/CatK-/-). This craniometry study aimed to highlight the craniofacial characteristics of oim and Cathepsin K KO mouse. MATERIALS AND METHODS: We analyzed the craniofacial skeleton of 51 mice distributed in 4 genotype groups: Wt (control), oim, CatK-/-, oim/CatK-/-. The mice were euthanized at 13 weeks and their heads were analyzed using densitometric (pQCT), X-ray cephalometric, and histomorphometric methods. RESULTS: The craniofacial skeleton of the oim mouse is frailer than the Wt one, with a reduced thickness and mineral density of the cranial vault and mandibular ramus. Different cephalometric data attest a dysmorphism similar to the one observed in humans with OI type III. Those abnormalities were not improved in the oim/CatK-/- group. CONCLUSION: These results suggest that oim mouse could serve as a complete model of the human OI type III, including the craniofacial skeleton. They also suggest that invalidation of cathepsin K has no impact on the craniofacial abnormalities of the oim model.

Diagnosis of Arboleda-Tham syndrome by whole-exome sequencing in an Asian girl with severe developmental delay.

OBJECTIVE: This study aims to report a severe phenotype of Arboleda-Tham syndrome in a 20-month-old girl, characterized by global developmental delay, distinct facial features, intellectual disability. Arboleda-Tham syndrome is known for its wide phenotypic spectrum and is associated with truncating variants in the KAT6A gene. METHODS: To diagnose this case, a combination of clinical phenotype assessment and whole-exome sequencing technology was employed. The genetic analysis involved whole-exome sequencing, followed by confirmation of the identified variant through Sanger sequencing. RESULTS: The whole-exome sequencing revealed a novel de novo frameshift mutation c.3048del (p.Leu1017Serfs*17) in the KAT6A gene, which is classified as likely pathogenic. This mutation was not found in the ClinVar and HGMD databases and was not present in her parents. The mutation leads to protein truncation or activation of nonsense-mediated mRNA degradation. The mutation is located within exon 16, potentially leading to protein truncation or activation of nonsense-mediated mRNA degradation. Protein modeling suggested that the de novo KAT6A mutation might alter hydrogen bonding and reduce protein stability, potentially damaging the protein structure and function. CONCLUSION: This study expands the understanding of the genetic basis of Arboleda-Tham syndrome, highlighting the importance of whole-exome sequencing in diagnosing cases with varied clinical presentations. The discovery of the novel KAT6A mutation adds to the spectrum of known pathogenic variants and underscores the significance of this gene in the syndrome's pathology.

Identifying Genetic Etiology in Patients with Intellectual Disability: An Experience in Public Health Services in Northeastern Brazil.

Intellectual disability (ID) is considered a common neuropsychiatric disorder that affects up to 3% of the population. The etiologic origin of ID may be genetic, environmental, and multifactorial. Chromosomopathies are relatively common among the genetic causes of ID, especially in the most severe cases and those associated with dysmorphic features. Currently, the application of new molecular cytogenetics technologies has increasingly allowed the identification of microdeletions, microduplications, and unbalanced translocations as causes of ID. The objective of this study was to investigate the etiology of ID in patients admitted to a public hospital in Northeastern Brazil. In total, 119 patients with ID who had normal karyotypes and fragile X exams participated in this study. The patients were initially physically examined for microdeletion syndromes and then tested using fluorescence in situ hybridization (FISH), multiplex ligation-dependent probe amplification (MLPA), methylation-sensitive polymerase chain reaction (MS-PCR), and chromosome microarray analysis (CMA), according to clinical suspicion. Patients with no diagnoses after FISH, MLPA, and/or MS-PCR evaluations were subsequently tested by CMA. The rate of etiologic diagnoses of ID in the current study was 28%. FISH diagnosed 25 out of 79 tested (31%), MLPA diagnosed 26 out of 79 tested (32%), MS-PCR diagnosed 7 out of 20 tested (35%), and the single nucleotide polymorphism array diagnosed 6 out of 27 tested (22%). Although the CMA is the most complete and recommended tool for the diagnosis of microdeletions, microduplications, and unbalance translocations in patients with ID, FISH, MLPA, and MS-PCR testing can be used as the first tests for specific syndromes, as long as the patients are first physically screened clinically, especially in the public health networks system in Brazil, where resources are scarce.

Klippel-Feil Syndrome With Isolated Facial Dysmorphism: A Clinical Conundrum With Resemblance to Adenoid Facies.

Klippel-Feil syndrome (KFS) is a triad comprising cervical spine fusion, a low posterior hairline, and constrained neck movement. This triad is not universally present. The most frequent accompaniment is Sprengel's scapula deformity. According to the Feil classification, Class 1 (C1) is an immense fusion of many cervical vertebrae, Class 2 (C2) is a fusion of one or two vertebrae only, and Class 3 (C3) is coupled with thoracic and lumbar spinal vertebral fusion in addition to the fusion of the cervical vertebrae. Clarke's categorization of KFS includes other associated anomalies. The different classification systems for KFS have been made by the different specialists to whom patients may present, which include orthopedic surgeons, neurosurgeons, orthodontists, faciomaxillary surgeons, cardiologists, and pediatricians. This anomaly being rare and the lack of universally accepted classification may lead to confusion regarding the identification of the syndrome, especially the Clarke Type 3 with isolated facial dysmorphism may go undiagnosed. We report a case with KFS-Clarke Type 3 with isolated facial dysmorphism and Feil Type 2 with the fusion of C2-C3 cervical vertebrae, detected as an incidental radiologic finding, and initial impression of adenoid facies. Hence, this case also highlights the contrasting features between the facial dysmorphism of Clarke Type 3 KFS and adenoid facies.

Mono-allelic KCNB2 variants lead to a neurodevelopmental syndrome caused by altered channel inactivation.

Ion channels mediate voltage fluxes or action potentials that are central to the functioning of excitable cells such as neurons. The KCNB family of voltage-gated potassium channels (Kv) consists of two members (KCNB1 and KCNB2) encoded by KCNB1 and KCNB2, respectively. These channels are major contributors to delayed rectifier potassium currents arising from the neuronal soma which modulate overall excitability of neurons. In this study, we identified several mono-allelic pathogenic missense variants in KCNB2, in individuals with a neurodevelopmental syndrome with epilepsy and autism in some individuals. Recurrent dysmorphisms included a broad forehead, synophrys, and digital anomalies. Additionally, we selected three variants where genetic transmission has not been assessed, from two epilepsy studies, for inclusion in our experiments. We characterized channel properties of these variants by expressing them in oocytes of Xenopus laevis and conducting cut-open oocyte voltage clamp electrophysiology. Our datasets indicate no significant change in absolute conductance and conductance-voltage relationships of most disease variants as compared to wild type (WT), when expressed either alone or co-expressed with WT-KCNB2. However, variants c.1141A>G (p.Thr381Ala) and c.641C>T (p.Thr214Met) show complete abrogation of currents when expressed alone with the former exhibiting a left shift in activation midpoint when expressed alone or with WT-KCNB2. The variants we studied, nevertheless, show collective features of increased inactivation shifted to hyperpolarized potentials. We suggest that the effects of the variants on channel inactivation result in hyper-excitability of neurons, which contributes to disease manifestations.

Identification of potential molecular mechanism related to craniofacial dysmorphism caused by FOXI3 deficiency.

BACKGROUND: Hemifacial macrosomia (HFM, OMIM 164210) is a complex and highly heterogeneous disease. FORKHEAD BOX I3 (FOXI3) is a susceptibility gene for HFM, and mice with loss of function of Foxi3 did exhibit a phenotype similar to craniofacial dysmorphism. However, the specific pathogenesis of HFM caused by FOXI3 deficiency remains unclear till now. METHOD: In this study, we first constructed a Foxi3 deficiency (Foxi3-/- ) mouse model to verify the craniofacial phenotype of Foxi3-/- mice, and then used RNAseq data for gene differential expression analysis to screen candidate pathogenic genes, and conducted gene expression verification analysis using quantitative real-time PCR. RESULTS: By observing the phenotype of Foxi3-/- mice, we found that craniofacial dysmorphism was present. The results of comprehensive bioinformatics analysis suggested that the craniofacial dysmorphism caused by Foxi3 deficiency may be involved in the PI3K-Akt signaling pathway. Quantitative real-time PCR results showed that the expression of PI3K-Akt signaling pathway-related gene Akt2 was significantly increased in Foxi3-/- mice. CONCLUSION: The craniofacial dysmorphism caused by the deficiency of Foxi3 may be related to the expression of Akt2 and PI3K-Akt signaling pathway. This study laid a foundation for understanding the function of FOXI3 and the pathogenesis and treatment of related craniofacial dysmorphism caused by FOXI3 dysfunction.

Deciphering congenital heart defects, facial dysmorphism and intellectual developmental disorder (CHDFIDD) associated with constitutional CDK13 pathogenic variants - case report and literature review.

There are 21 human cyclin-dependent kinases which are involved in regulation of the cell cycle, transcription, RNA splicing, apoptosis and neurogenesis. Five of them: CDK4, CDK5, CDK6, CDK10 and CDK13 are associated with human phenotypes. To date, only 62 patients have been presented with mutated CDK13 gene. Those patients had developmental delay, dysmorphic facial features, feeding difficulties, different structural heart and brain defects. 36 of them had missense mutation affecting the protein kinase domain of CDK13. Our patient is the first person reported so far with a frameshift mutation which introduce premature stop codon in the first exon of the CDK13 gene. She has symptoms characteristic for congenital heart defects, facial dysmorphism and intellectual developmental disorder (CHDFIDD).

Hashimoto's Thyroiditis in Noonan Syndrome: A Case Report.

Noonan syndrome is a genetic, developmental disorder characterized by facial deformities, congenital heart defects, webbed neck, wide space nipples, and growth hormone deficiencies. We report a case of a 15-year-old female patient who presented to the outpatient department with recurrent puffiness of both eyes, easy fatiguability, and dyspnea on exertion. The condition was associated with bilateral proximal muscular weakness of lower limbs with positive Gower's sign. On examination, the patient had a webbed neck, hypertelorism, a shielded chest, short stature, and a high-arched palate. Thyroid function tests revealed hypothyroidism. Chromosomal analysis revealed 46 XX. After excluding Turner syndrome on karyotyping, Noonan syndrome with hypothyroidism was diagnosed. The patient was started on levothyroxine and referred to a pediatric endocrinologist for further growth and development assessment. Autoimmune hypothyroidism in a patient with Noonan Syndrome is rare; it may occur as a separate entity or have some genetic susceptibility. Further research is needed to determine the association of autoimmune hypothyroidism with Noonan syndrome.

[Translated article] Insertion of S1 iliosacral screws in the computed tomography room: An alternative to improve safety in the percutaneous management of posterior pelvic ring injuries.

INTRODUCTION: The main complication of percutaneous iliosacral screw fixation is implant malposition, which can lead to vascular and nerve damage. The anatomical variability of the sacrum can make screw insertion difficult under fluoroscopic guidance. Among the methods described to improve the accuracy of this technique, stands out the use of computed tomography (CT). The aim of this study is to compare the results of iliosacral screw insertion with fluoroscopy or CT navigation. METHODOLOGY: Retrospective cohort study of 66 iliosacral screws in 56 patients during 11 years. The screws were inserted with fluoroscopy in the operating room or with CT in the radiodiagnosis area. We collected data on patient characteristics, lesions, treatment, and clinical and radiological results. RESULTS: Forty-seven screws were inserted with fluoroscopy and 19 with CT. A percentage of 18.2 of screws perforated the S1 osseous corridor. All of them were inserted with fluoroscopy guidance (0 vs. 34%; p<0.01). Those operated with CT accumulated more sacral dysmorphism criteria than those operated with fluoroscopy (2.2 vs. 1.6; p=0.02). The S1 corridor on the axial CT view was narrower in those in whom perforation had occurred (18.8 vs. 21.0mm; p=0.02). Two cases with perforation developed S1 radiculalgia. Two endopelvic screws had to be removed. CONCLUSION: We advise the use of CT guidance for iliosacral screw insertion in patients with sacral dysmorphism or narrow S1 corridors in facilities where other navigation methods are not available.

DLG2 intragenic exonic deletions reinforce the link to neurodevelopmental disorders and suggest a potential association with congenital anomalies and dysmorphism.

PURPOSE: Multiple studies suggest an association between DLG2 and neurodevelopmental disorders and indicate the haploinsufficiency of this gene; however, few cases have been thoroughly described. We performed additional studies to confirm this clinical association and DLG2 haploinsufficiency. METHODS: Chromosomal microarray analysis was performed on 11,107 patients at the Cytogenetics Laboratory at the University of Alabama at Birmingham. The Database of Genomic Variants-Gold Standard Variants and the Genome Aggregation Database were selected for the association analysis. Fifty-nine patients from the literature and DECIPHER, all having DLG2 intragenic deletions, were included for comprehensive analysis of the distribution of these deletions. RESULTS: A total of 13 patients with DLG2 intragenic deletions, from 10 families in our cohort, were identified. Nine of 10 probands presented with clinical features of neurodevelopmental disorders. Congenital anomalies and dysmorphism were common in our cohort of patients. Association analysis showed that the frequency of DLG2 deletions in our cohort is significantly higher than those in the Database of Genomic Variants-Gold Standard Variants and the Genome Aggregation Database. Most of DLG2 intragenic deletions identified in 69 unrelated patients from our cohort, the literature, and DECIPHER map to the 5' region of the gene, with a hotspot centered around HPin7, exon 8, and HPin8. CONCLUSION: Our findings reinforce the link between DLG2 intragenic deletions and neurodevelopmental disorders, strongly support the haploinsufficiency of this gene, and indicate that these deletions might also have an association with congenital anomalies and dysmorphism.