Bromodomain PHD finger transcription factor (BPTF) is the largest subunit of nucleosome remodeling factor (NURF), a member of the ISWI chromatin-remodeling complex. However, the clinical consequences of disruption of this complex remain largely uncharacterized. BPTF is required for anterior-posterior axis formation of the mouse embryo and was shown to promote posterior neuroectodermal fate by enhancing Smad2-activated wnt8 expression in zebrafish. Here, we report eight loss-of-function and two missense variants (eight de novo and two of unknown origin) in BPTF on 17q24.2. The BPTF variants were found in unrelated individuals aged between 2.1 and 13 years, who manifest variable degrees of developmental delay/intellectual disability (10/10), speech delay (10/10), postnatal microcephaly (7/9), and dysmorphic features (9/10). Using CRISPR-Cas9 genome editing of bptf in zebrafish to induce a loss of gene function, we observed a significant reduction in head size of F0 mutants compared to control larvae. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and phospho-histone H3 (PH3) staining to assess apoptosis and cell proliferation, respectively, showed a significant increase in cell death in F0 mutants compared to controls. Additionally, we observed a substantial increase of the ceratohyal angle of the craniofacial skeleton in bptf F0 mutants, indicating abnormal craniofacial patterning. Taken together, our data demonstrate the pathogenic role of BPTF haploinsufficiency in syndromic neurodevelopmental anomalies and extend the clinical spectrum of human disorders caused by ablation of chromatin remodeling complexes.

Neurodevelopmental disorder with dysmorphic facies and distal limb anomalies (NEDDFL), defined primarily by developmental delay/intellectual disability, speech delay, postnatal microcephaly, and dysmorphic features, is a syndrome resulting from heterozygous variants in the dosage‐sensitive bromodomain PHD finger chromatin remodeler transcription factor BPTF gene. To date, only 11 individuals with NEDDFL due to de novo BPTF variants have been described. To expand the NEDDFL phenotypic spectrum, we describe the clinical features in 25 novel individuals with 20 distinct, clinically relevant variants in BPTF, including four individuals with inherited changes in BPTF. In addition to the previously described features, individuals in this cohort exhibited mild brain abnormalities, seizures, scoliosis, and a variety of ophthalmologic complications. These results further support the broad and multi‐faceted complications due to haploinsufficiency of BPTF.

BackgroundAs mucopolysaccharidosis IVA (MPS IVA) is the most frequent MPS in Colombia, this paper aims to describe its clinical and mutational characteristics in 32 diagnosed patients included in this study.MethodsGenotyping was completed by amplification and Sanger sequencing of the GALNS gene. The SWISS-model platform was used for bioinformatic analysis, and mutant proteins were generated by homology from the wild-type GALNS code 4FDI template from the Protein Data Bank (PDB) database. Docking was performed using the GalNAc6S ligand (PubChem CID: 193456) by AutoDock Vina 1.0 and visualized in PyMOL and LigPlot+.ResultsEleven variants were identified, and one new pathogenic variant was described in the heterozygous state, which is consistent with genotype c. 319 G> T or p.Ala107Ser. The pathogenic variant c.901G>T or p.Gly301Cys was the most frequent mutation with 51.6% of alleles. Docking revealed affinity energy of −5.9 Kcal/mol between wild-type GALNS and the G6S ligand. Some changes were evidenced at the intermolecular interaction level, and affinity energy for each mutant decreased.ConclusionClinical variables and genotypic analysis were similar to those reported for other world populations. Genotypic data showed greater allelic heterogeneity than those previously reported. Bioinformatics tools showed differences in the binding interactions of mutant proteins with the G6S ligand, in regard the wild-type GALNS.

Case Presentation: Pelizaeus Merzbacher Disease (PMD) is an X-linked developmental defect of myelination that causes childhood chronic spastic encephalopathy. Its genetic etiology can be either a duplication (or other gene dosage alterations) or a punctual mutation at the PLP1 locus. Clinically, it presents with developmental delay, nystagmus and, spasticity, supported by neuroimaging in which the defect of myelination is evident. We present a series of seven Colombian patients diagnosed with this leucodystrophy, describing their genotypic and phenotypic characteristics and heterogeneity.Clinical Findings: All patients included were male, 6 months to 16 years of age. Mean age at onset of symptoms was 8 months. Mean age at diagnosis was 5 years 5 months, being classic PMD most frequently diagnosed, as compared to the connatal phenotype. All cases had a primary diagnosis of developmental delay on 100%, and in 28.7% of cases, early onset nystagmus was described. 85.7% of patients had spasticity, 71.4% cerebellar signs, 57.0% hypotonia, and 28.5% had an abnormal movement disorder. Only three patients were able to achieve gait, though altered. In the two patients who had a diagnosis of connatal PMD maturational ages in danger zones according to the WHO Abbreviated Scale of Psychosocial Development were documented. All cases had abnormalities in neuroimages. Molecular Analysis and Results: Molecular studies were used in the majority of the cases to confirm the diagnosis (85.7 %). For two cases molecular confirmation was not considered necessary given their affected male brothers had already been tested. PLP1 gene dosage alterations (duplications) were found in 28.5 % of the patients (two siblings), whereas three different single nucleotide variants were detected.Clinical Relevance: According to these findings, as authors we propose the diagnostic algorithm in Colombian population to begin on a high clinical suspicion, followed by paraclinical extension, moving on to the molecular confirmation by using approaches to simultaneously sequence the PLP1 gene in order to detect point mutations and in/dels and performing a copy number variation analysis for the detection of gene dosage alterations.

Objetivo: analizar los grados de discapacidad y las implicaciones médicas, sociales y económicas de las anomalías congénitas y las enfermedades genéticas en los pacientes de consulta de genética médica de un hospital de segundo nivel de atención en Colombia.<br />Métodos: se realizó un estudio descriptivo de 169 pacientes de la consulta de genética médica de un hospital de 2° nivel de atención, analizando las variables demográficas, los principales motivos de consulta según frecuencia, la etiología de dichas enfermedades; adicionalmente se realizó un análisis de los estudios citogenéticos y número de controles de la población a estudio; finalmente se realizó el análisis de la clasificación según pronóstico de discapacidad y según la intervención oportuna y adecuada para cada enfermedad. Resultados: se encontró una distribución por sexo de 59% mujeres y 41% hombres, los tres principales motivos de consulta fueron: asesoría genética por antecedentes de hijos con malformaciones congénitas o enfermedades genéticas (10%), seguido de baja talla y Síndrome de Down (8% cada uno). En la distribución etiológica e4% de los pacientes tienen diagnóstico final de enfermedades de origen genético mendeliano o cromosómico, el resto de pacientes corresponden a entidades de etiología multifactorial y ambiental. Finalmente según la clasificación del pronóstico de discapacidad, el 92,6% de esta población presenta algún grado de discapacidad prevenible y tratable y deben ser intervenidos oportunamente.<br />Conclusiones: los autores planteamos la posibilidad de llevar a hospitales de segundo nivel de atención médica el ejercicio de la genética clínica, debido a que la enfermedad congénita y genética es frecuente, requiere un temprano diagnóstico y oportuno tratamiento, impacta de manera importante en la salud pública y hace necesario afrontar el proceso de transición epidemiológica desde todos los frentes, llamando la atención de entes territoriales y gubernamentales demostrando la importancia de servicios adecuados de genética clínica.

Introduction: Mucopolysaccharidosis type VI, also known as Maroteaux-Lamy syndrome (#OMIM 253200), is a rare autosomal recessive genetic disorder due to deficient activity of the enzyme N-acetylgalactosamine 4-sulfatase (arylsulfatase B) required for the breakdown of dermatan sulfate and chondroitin sulfate. Patient: Report of a female patient started on enzyme replacement therapy at 17 months of age. At the time of diagnosis (14 months), the patient presented mild corneal opacity and significant thoracolumbar kyphosis, but no visceral involvement or growth arrest. At 73 months of treatment, weight was normal, although the patient was in a low height percentile. The patient showed adequate neural development, with improvement in lumbar spine and joint involvement. Corneal compromise or valvular disease progression was not evident. Conclusion: Early and timely diagnosis and treatment with enzyme replacement therapy are essential, as the means to change the natural history of the disease, avoiding comorbidities and improving final prognosis.

Las distrofias musculares congénitas son entidades con herencia autosómica recesiva. Se clasifican en las que comprometen el sistema nervioso central y las que no lo hacen (forma clásica). Este último grupo se subdivide en distrofias sin déficit de merosina y con déficit de merosina.Se reporta el caso de un paciente con hipotonía grave, contracturas articulares y compromiso de la sustancia blanca del sistema nervioso central. Se considera el diagnóstico de distrofia muscular congénita con posible déficit de merosina.

Presentación de casos clínicos RESUMENLa combinación del síndrome de Turner con otros trastornos genéticos, como la catarata congénita, ha sido reportada. Sin embargo, su asociación con una forma de catarata nuclear congénita con herencia autosómica dominante y penetrancia incompleta no ha sido reportada previamente en la literatura. Tampoco existen reportes de su presentación junto con rearreglos en el cromosoma 17. A continuación, presentamos el excepcional caso de una paciente con una constelación de anomalías mayores y menores, diagnosticada con síndrome de Turner en mosaico por isocromosoma Xq, asociado a una microduplicación 17p13.3p13.2, quien además presenta catarata nuclear congénita bilateral de herencia autosómica dominante con penetrancia incompleta. Se realiza una revisión acerca del origen y la causa de estas alteraciones genéticas y una aproximación a la hipótesis de la patogénesis de la asociación de dos de estos trastornos genéticos en una misma paciente. Palabras clave: síndrome de Turner, isocromosoma Xq, catarata congénita, mosaicismo cromosómico, microduplicación 17p. ABSTRACTThe combination of Turner syndrome with other genetic disorders such as congenital cataract has been reported, but its association with a congenital form with autosomal dominant inheritance and incomplete penetrance has not been previously reported in the literature. There are no reports on its presentations with rearrangements on chromosome 17. We report the exceptional case of a 20 months old girl with a constellation of major and minor anomalies, diagnosed with mosaic Turner syndrome by isochromosome Xq associated with a microduplication 17p13.3p13.2, who also had bilateral congenital nuclear cataract autosomal dominant with incomplete penetrance. We reviewed in the literature the origin and cause of these genetic alterations and we provided an Isocromosoma Xq en mosaico y microduplicación 17p13.3p13.2 en una paciente con síndrome de Turner y catarata congénita Mosaic isochromosome Xq and microduplication 17p13.3p13.2 in a patient with Turner syndrome and congenital cataract approach to the hypothesis of the pathogenesis of the association of two of these genetic disorders in the same patient.