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Sumaiya Adam,1 Melantha Coetzee,2 Engela Magdalena Honey3 1Department of Obstetrics and Gynaecology, Steve Biko Academic Hospital, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa; 2Division of Neonatology, Department of Pediatrics and Child Health, Steve Biko Academic Hospital, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa; 3Department of Biochemistry, Genetics and Microbiology, Faculty of Natural and Agricultural Sciences, University of Pretoria, Pretoria, South Africa Abstract: Pena–Shokeir syndrome (PSS) type 1, also known as fetal akinesia deformation sequence, is a rare genetic syndrome that almost always results in intrauterine or early neonatal death. It is characterized by markedly decreased fetal movements, intrauterine growth restriction, joint contractures, short umbilical cord, and features of pulmonary hypoplasia. Antenatal ­diagnosis can be difficult. Ultrasound features are varied and may overlap with those of ­Trisomy 18. The poor prognosis of PSS is due to pulmonary hypoplasia, which is an important feature that distinguishes PSS from arthrogryposis multiplex congenital without pulmonary hypoplasia, which has a better prognosis. If diagnosed in the antenatal period, a late termination of pregnancy can be considered following ethical discussion (if the law allows). In most cases, a diagnosis is only made in the neonatal period. Parents of a baby affected with PSS require detailed counseling that includes information on the imprecise recurrence risks and a plan for subsequent pregnancies. Keywords: fetal akinesia deformation sequence, ultrasound, comfort care

Persistent congenital hyperinsulinism (HI) is a rare genetically heterogeneous condition characterised by dysregulated insulin secretion leading to life-threatening hypoglycaemia. For up to 50% of affected individuals screening of the known HI genes does not identify a disease-causing variant. Large deletions have previously been used to identify novel regulatory regions causing HI. Here, we used genome sequencing to search for novel large (>1 Mb) deletions in 180 probands with HI of unknown cause and replicated our findings in a large cohort of 883 genetically unsolved individuals with HI using off-target copy number variant calling from targeted gene panels. We identified overlapping heterozygous deletions in five individuals (range 3-8 Mb) spanning chromosome 20p11.2. The pancreatic beta-cell transcription factor gene, FOXA2, a known cause of HI was deleted in two of the five individuals. In the remaining three, we found a minimal deleted region of 2.4 Mb adjacent to FOXA2 that encompasses multiple non-coding regulatory elements that are in conformational contact with FOXA2. Our data suggests that the deletions in these three children may cause disease through the dysregulation of FOXA2 expression. These findings provide new insights into the regulation of FOXA2 in the beta-cell and confirm an aetiological role for chromosome 20p11.2 deletions in syndromic HI., (© 2024. The Author(s).)

Introduction: Maternally inherited diabetes and deafness (MIDD) is caused by the m.3243A>G pathogenic variant in maternally inherited mitochondrial DNA. Diabetes is prevalent in our setting; however, MIDD is rarely diagnosed. This study, undertaken in Pretoria, South Africa, highlights the variable presentation of MIDD in different patients within the same family., Case Presentation: A 45-year-old man (proband) with hearing impairment was referred to the endocrine unit in July 2015 due to poor glycaemic control (HbA1c = 13%). His clinical and biochemical features were in keeping with MIDD. A genetic study of accessible maternal relatives was pursued. His mother had difficulty hearing and reportedly died from an unspecified cardiovascular cause. Two sisters with diabetes and deafness died of cardiac-related conditions. One nephew had diabetes (HbA1c = 7.7%), hearing loss and tested positive for m.3243A>G. A third sister tested positive for m3243A>G, but aside from bilateral mild hearing loss in higher frequencies, showed no other signs of target organ damage. Her daughter developed end-stage kidney failure necessitating a transplant, while her son had no biochemical abnormalities and was negative for m.3243A>G., Management and Outcome: A multidisciplinary team managed and screened for complications of the patient and his maternal relatives. Proband died prior to genetic testing., Conclusion: Most MIDD patients initially present with symptoms of diabetes only, and it is probable that many cases remain undiagnosed. A high index of suspicion is necessary when encountering a family history of both diabetes and impaired hearing, and screening should be offered to the patient's maternal relatives., What the Study Adds: This study demonstrates the importance of proper assessment when evaluating a patient with diabetes and a family history of hearing loss., Competing Interests: The authors declare that they have no financial or personal relationship(s) that may have inappropriately influenced them in writing this article., (© 2024. The Authors.)

Computer-aided facial diagnostic tools are valuable emerging technologies for the early detection and initial diagnosis of congenital disorders. These tools require large datasets of facial photographs, especially of infants and children, to identify these disorders and improve classification accuracies. Researchers need to balance this need for larger datasets with patients' privacy rights, needs and preferences. This study aimed to investigate parents' views regarding the collection, storage, use and publication of their children's facial images for research and diagnostic purposes. A total of 151 parents of children with and without congenital disorders completed an online survey evaluating their views on the collection, storage, use and publication of children's facial images for research and diagnosis. Overall, 72.5% of parents would allow researchers to take facial photographs of their children, preferring the images to be stored in a secure database that is not available to the public. Parents of children with congenital disorders were more accepting of researchers taking facial photographs of their children, compared to parents of children without these conditions. Half of the respondents would allow facial photographs of their children to be published in academic journals, without their eyes covered, and this acceptance increased as the proportion of the child's face covered increased. Parents also indicated specific requirements to allow the use of these images in other similar research studies which need to be taken into consideration when planning studies that involve facial analysis research., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: Application of whole genome sequencing (WGS) enables identification of non-coding variants that play a phenotype-modifying role and are undetectable by exome sequencing. Recently, non-coding regulatory single nucleotide variants (SNVs) have been reported in patients with lethal lung developmental disorders (LLDDs) or congenital scoliosis with recurrent copy-number variant (CNV) deletions at 17q23.1q23.2 or 16p11.2, respectively., Case Presentation: Here, we report a deceased newborn with pulmonary hypertension and pulmonary interstitial emphysema with features suggestive of pulmonary hypoplasia, resulting in respiratory failure and neonatal death soon after birth. Using the array comparative genomic hybridization and WGS, two heterozygous recurrent CNV deletions: ~ 2.2 Mb on 17q23.1q23.2, involving TBX4, and ~ 600 kb on 16p11.2, involving TBX6, that both arose de novo on maternal chromosomes were identified. In the predicted lung-specific enhancer upstream to TBX4, we have detected seven novel putative regulatory non-coding SNVs that were absent in 13 control individuals with the overlapping deletions but without any structural lung anomalies., Conclusions: Our findings further support a recently reported model of complex compound inheritance of LLDD in which both non-coding and coding heterozygous TBX4 variants contribute to the lung phenotype. In addition, this is the first report of a patient with combined de novo heterozygous recurrent 17q23.1q23.2 and 16p11.2 CNV deletions.

Context: Cleft patients with Holoprosencephaly (HPE) constitute a controversy due to a variable facial appearance. HPE appearance varies from only a columella to a prolabium-premaxilla complex agenesis up to a common unilateral or bilateral cleft lip and palate with a single central incisor, various brain deformities, and/or even normal brain development. It is challenging to designate such various appearances, to understand their etiopathogenesis, and to choose the most appropriate management. Literature was reviewed for diagnostic criteria, pregnancy history, clinical findings, brain development, survival rate, initial perioperative management, and postsurgical midfacial growth in cleft patients with HPE. The findings were compared with a clinical database of 85 cleft patients with HPE at the Department of Maxillofacial and Oral Surgery, University of Pretoria., Aims of Part 1: The aim of the study is to overcome disparities widely existing among clinicians regarding definitive diagnostic criteria, especially in cases with a common appearance of a uni- or bilateral cleft lip alveolus or cleft lip, alveolus and palate deformity, and cases presenting facial structural agenesis., Materials and Methods: A literature search related to diagnostic criteria was compared to results of a cleft HPE database from a single tertiary institution., Results: HPE cleft cases can be allocated to one of the following subdivisions: (1) columella complex agenesis (Ag-Colum), (2) prolabium-premaxilla-columella complex agenesis in cleft lip-alveolus deformities (Ag-CLA), (3) prolabium-premaxilla-columella agenesis in cases with complete cleft lip alveolus palate (Ag-CLAP), and (4) standard type (holoprosencephaly in patients with a standard cleft) with uni- or bilateral CLA or CLAP, hard and soft palate cleft (hPsP), and atrophic premaxillae, with or without single central incisor. Further, incidence, variation in brain development, and appearances in HPE cleft patients of different races and gender, epilepsy, and early death are discussed. Conclusion: This paper adds new data and facts to the existing literature related to cleft lip and palate patients suffering from HPE., Competing Interests: There are no conflicts of interest.

Spondyloepimetaphyseal dysplasia with joint laxity (SEMD-JL) is an autosomal recessive skeletal dysplasia in which stunted stature, articular hypermobility and spinal malalignment are the major manifestations. Structural cardiac abnormalities are sometimes present. Approximately 30 affected children have been recognised previously in the Afrikaans-speaking community in South Africa, and in several, mutations in the B3GALT6 gene have been incriminated. In this article, case details of three additional affected children in two families are documented, and four additional families are mentioned. The Pierre-Robin sequence and unilateral renal agenesis are previously unreported concomitants. The mutational status where known is recorded.

Autosomal dominantly inherited oculopharyngeal muscular dystrophy (OPMD) is caused by a trinucleotide repeat expansion in exon 1 of the polyadenylate binding protein nuclear 1 (PABPN1) gene on chromosome 14q. A large family with OPMD was recently identified in Pretoria, South Africa (SA). Molecular studies revealed a (GCG)11(GCA)3GCG or (GCN)15 mutant allele. The (GCN)15 mutation detected in this family has been described previously in families from Uruguay and Mexico as a founder effect. To our knowledge, this is the first report of an SA Afrikaner family with molecularly confirmed OPMD. The proband, a 64-year-old woman, presented to the neurology outpatient department at Steve Biko Academic Hospital, Pretoria. A sibship of 18 individuals was identified, of whom eight had OPMD. Four patients were interviewed and examined clinically, and electromyographic studies were performed. Molecular analysis of the PABPN1 gene was performed by polymerase chain reaction amplification and direct sequencing of exon 1 in three of the patients. Patients presented with ptosis, external ophthalmoplegia, dysphagia, dysarthria and mild proximal weakness. High foot arches and absent ankle reflexes raised the possibility of peripheral neuropathy, but electromyography showed only mildly low sensory amplitudes, and myopathic units in two patients.

Background: Floating-Harbor syndrome (FHS) is a rare condition characterized by short stature, delays in expressive language, and a distinctive facial appearance. Recently, heterozygous truncating mutations in SRCAP were determined to be disease-causing. With the availability of a DNA based confirmatory test, we set forth to define the clinical features of this syndrome., Methods and Results: Clinical information on fifty-two individuals with SRCAP mutations was collected using standardized questionnaires. Twenty-four males and twenty-eight females were studied with ages ranging from 2 to 52 years. The facial phenotype and expressive language impairments were defining features within the group. Height measurements were typically between minus two and minus four standard deviations, with occipitofrontal circumferences usually within the average range. Thirty-three of the subjects (63%) had at least one major anomaly requiring medical intervention. We did not observe any specific phenotype-genotype correlations., Conclusions: This large cohort of individuals with molecularly confirmed FHS has allowed us to better delineate the clinical features of this rare but classic genetic syndrome, thereby facilitating the development of management protocols.

ALG6-CDG (formerly named CDG-Ic) (phenotype OMIM 603147, genotype OMIM 604566), is caused by defective endoplasmic reticulum α-1,3-glucosyltransferase (E.C 2.4.1.267) in the N-glycan assembly pathway (Grünewald et al. 2000). It is the second most frequent N-glycosylation disorder after PMM2-CDG; some 37 patients have been reported with 21 different ALG6 gene mutations (Haeuptle & Hennet 2009; Al-Owain 2010). We report on the clinical and biochemical findings of five novel Caucasian South African patients. The first patient had a severe neuro-gastrointestinal presentation. He was compound heterozygous for the known c.998C>T (p.A333V) mutation and the novel c.1338dupA (p.V447SfsX44) mutation. Four more patients, presenting with classical neurological involvement were identified and were compound heterozygous for the known c.257 + 5G>A splice mutation and the c.680G>A (p.G227E) missense mutation. The patients belong to a semi-isolated Caucasian community that may have originated from European pioneers who colonized South Africa in the seventeenth/eighteenth centuries.

Zimmermann-Laband syndrome (ZLS) is a very rare autosomal dominant inherited condition characterized by 3 major clinical findings of which gingival hyperplasia are always present. The great heterogenicity of the syndrome is illustrated by the numerous variable clinical findings described in the literature. The purpose of the study was to examine a patient diagnosed with ZLS and to describe possible new characteristics of this rare syndrome, including the ultrastructural morphology using a transmission electron microscope (TEM) of the gingival and dermal fibroblasts. The ultrastrucutral morphology as has not previously been described in the literature. Tissue was collected from the alveolar ridge and skin of the forearm for TEM. TEM studies indicated the presence of prominent fibroblasts situated among numerous regular dense connective tissue bundles. Genetic analysis showed a new chromosomal insertion, ins(12;8)(p11.2;q11.2q24.3), suggesting that the gene responsible for the syndrome lies on chromosome 8.

Branchio-oto-renal (BOR) syndrome is an autosomal dominant disorder characterized by the associations of hearing loss, branchial arch defects and renal anomalies. Branchiootic (BO) syndrome is a related disorder that presents without the highly variable characteristic renal anomalies of BOR syndrome. Dominant mutations in the human homologue of the Drosophila eyes absent gene (EYA1) are frequently the cause of both BOR and BO syndromes. We report a South African family of Afrikaner descent with affected individuals presenting with pre-auricular abnormalities and either hearing loss or bilateral absence of the kidneys. Genetic analysis of the pedigree detected a novel EYA1 heterozygous nonsense mutation in affected family members but not in unaffected family members or a random DNA panel. Through mutational analysis, we conclude that this particular mutation is the cause of BOR/BO syndrome in this family as a result of a truncation of the EYA1 protein that ablates the critical EYA homologous region. To the best of our knowledge, this is the first case of BOR/BO syndrome reported in Africa or in those of the Afrikaner descent.

We report an interesting feature in the consecutive steps of coalescing of a drop, which is called a cascade of partial coalescence. It is observed that as the secondary drop gets smaller, it bounces higher. We show that the capillary force is the main driving force for this phenomenon. By using ultra-high-speed video, it is revealed that the capillary force at the pinch off pulls the drop to the planar interface. The drop bounces off the interface and moves upward until it reaches the maximum height. A theory is developed that includes the capillary and gravitational forces and predicts this process.

Spondyloenchondromatosis (SEM) is a rare skeletal dysplasia which presents with multiple enchondromata in the metaphyses of the long bones associated with dysplastic vertebral bodies. It is probably heterogeneous. We have investigated and documented a male infant in South Africa with spondyloenchondromatosis and persistent D-2-hydroxyglutaric aciduria (D2HA). D2HA is a neurometabolic disorder whose enzymatic basis is still undefined. A girl in England with a similar clinical, radiological and biochemical phenotype has previously been reported by Talkhani et al. [(2000). Skel Radiol 7:215-2921]. There is at present a lack of a plausible pathogenetic relationship between the two components of the disorder but a contiguous gene syndrome or a pleiotropic gene could be considered. Whatever the underlying mechanism this case report confirms its nosological entity.

Raised intracranial pressure (ICP) often complicates the course of cryptococcal meningitis. The pathogenesis of the severely raised cerebrospinal fluid (CSF) pressure commonly associated with this condition is largely unexplained, because the majority of patients have normal cranial computed tomographic (CT) findings when diagnosed. We report a case of cryptococcal meningitis in a child who had severely raised CSF pressure on admission, and in whom repeated CT scanning showed progressive enlargement of the subarachnoid space and ventricular system during the course of treatment. The normalization of these spaces after ventriculoperitoneal (VP) shunting suggests a distal CSF block as the cause of the raised ICP in this patient. The CSF pressure was monitored and treatment with oral acetazolamide and furosemide resulted in a definite, but slow and incomplete lowering of ICP. Intrathecal therapy with hyaluronidase had no beneficial effect on either ICP or the degree of visual loss.