Broadening the phenotypic spectrum of POP1-skeletal dysplasias: identification of POP1 mutations in a mild and severe skeletal dysplasia.

Processing of Precursor 1 (POP1) is a large protein common to the ribonuclease-mitochondrial RNA processing (RNase-MRP) and RNase-P (RMRP) endoribonucleoprotein complexes. Although its precise function is unknown, it appears to participate in the assembly or stability of both complexes. Numerous RMRP mutations have been reported in individuals with cartilage-hair hypoplasia (CHH) but, to date, only three POP1 mutations have been described in two families with features similar to anauxetic dysplasia (AD). We present two further individuals, one with severe short stature and a relatively mild skeletal dysplasia and another in whom AD was suspected. Biallelic POP1 mutations were identified in both. A missense mutation and a novel single base deletion were detected in proband 1, p.[Pro582Ser]:[Glu870fs*5]. Markedly reduced abundance of RMRP and elevated levels of pre5.8s rRNA was observed. In proband 2, a homozygous novel POP1 mutation was identified, p.[(Asp511Tyr)];[(Asp511Tyr)]. These two individuals show the phenotypic extremes in the clinical presentation of POP1-dysplasias. Although CHH and other skeletal dysplasias caused by mutations in RMRP or POP1 are commonly cited as ribosomal biogenesis disorders, recent studies question this assumption. We discuss the past and present knowledge about the function of the RMRP complex in skeletal development.

Analysis of FOXP3 gene in children with allergy and autoimmune diseases.

BACKGROUND: Allergy and autoimmunity are important immunological entities underlying chronic diseases in children. In some cases both entities develop simultaneously in the same patient. FOXP3 gene codes for a transcription factor involved in regulation of the immune system. Considering that regulatory T cells are involved in controlling immunological disease development, and the relevant role of FOXP3 in this kind of T cells, the objective of this study was to analyse the FOXP3 gene in the most prevalent autoimmune diseases and/or allergies in childhood in a European population. METHODS: A total of 255 Caucasian individuals, 95 controls and 160 patients diagnosed with allergic, autoimmune or both diseases were included in this study. The molecular analysis of FOXP3 was performed by DNA sequencing following the recommendations for quality of the European Molecular Genetics Quality Network. Genomic DNA was extracted from peripheral blood of all participants and was amplified using the polymerase chain reaction. After the visualisation of the amplified fragments by agarose gel-electrophoresis, they were sequenced. RESULTS: Thirteen different polymorphisms in FOXP3 gene were found, seven of which had not been previously described. The mutated allele of SNP 7340C>T was observed more frequently in the group of male children suffering from both allergic and autoimmune diseases simultaneously (p=0.004, OR=16.2 [1.34-195.15]). CONCLUSIONS: In this study we identified for first time genetic variants of FOXP3 that are significantly more frequent in children who share allergic and autoimmune diseases. These variants mainly affect regulatory sequences that could alter the expression levels of FOXP3 modifying its function including its role in Treg cells.

[Neonatal seizures and progression to epilepsy in a tertiary hospital]. / Crisis neonatales y evolución a epilepsia en un hospital de tercer nivel.

INTRODUCTION: Given the immaturity of the newborn, neonatal seizures are a diagnostic challenge. Most of them are secondary to an acute event. A small percentage constitute the onset of epilepsy. AIMS: The aim was to analyse neonates with a diagnosis of seizures admitted to a tertiary hospital between November 2009 and May 2021, and their subsequent progression to epilepsy. MATERIAL AND METHODS: A retrospective observational study was carried out using the hospital database. Information was collected on neonates with a discharge diagnosis of 'seizures' or 'moderate or severe hypoxic-ischaemic encephalopathy'. Different variables were analysed: aetiology of the seizures, type, persistence over time, treatment and electroclinical correlates. RESULTS: Of 165 patients, 55 presented neonatal seizures. As regards aetiology, 43 patients (78%) had seizures secondary to an acute event, of which 19 (34%) were hypoxic-ischaemic encephalopathies, and 22 (40%) had other acute disorders. Genetic alteration was found in six of them (11%). Thirteen patients (24%) progressed to subsequent epilepsy, of whom seven had symptomatic epilepsy, with a period of latency after the acute event in two patients. Six patients had neonatal epilepsy with unprovoked seizures. Twenty-two (62%) showed electroclinical correlates. All of the confirmed crises (100%) were focal. All the seizures were treated. The drug of choice was phenobarbital. CONCLUSIONS: Diagnosis of neonatal seizures requires high clinical suspicion and electroclinical confirmation. Most of them progress favourably, but a percentage constitute the onset of epilepsy, the identification of which will determine their therapeutic management.

TITLE: Crisis neonatales y evolución a epilepsia en un hospital de tercer nivel.Introducción. Las convulsiones neonatales son un reto diagnóstico, dada la inmadurez del recién nacido. La mayoría son secundarias a un evento agudo. Un pequeño porcentaje constituye el inicio de una epilepsia. Objetivos. Analizar a los neonatos ingresados en un hospital de tercer nivel con diagnóstico de crisis entre noviembre de 2009 y mayo de 2021, y su evolución posterior a epilepsia. Material y métodos. Se ha realizado un estudio observacional retrospectivo utilizando la base de datos del hospital. Se ha recogido la información de los neonatos con diagnóstico en el alta de 'convulsiones' o 'encefalopatía hipóxico-isquémica moderada o grave'. Se analizaron distintas variables: etiología de las crisis, tipo, persistencia temporal, tratamiento y correlato electroclínico. Resultados. De 165 pacientes, 55 presentaron crisis neonatales. En cuanto a la etiología, 43 pacientes (78%) tuvieron crisis secundarias a un evento agudo, de las cuales 19 (34%) fueron encefalopatías hipóxico-isquémicas, y 22 (40%), otras alteraciones agudas. En seis (11%) se encontró alteración genética. Trece pacientes (24%) evolucionaron a una epilepsia posterior, de los cuales siete presentaron una epilepsia sintomática, con un período de latencia tras el evento agudo en dos pacientes. Seis pacientes tuvieron epilepsia neonatal con crisis no provocadas. Veintidós (62%) mostraron correlato electroclínico. El 100% de las crisis confirmadas fueron focales. Todas las crisis se trataron. El fármaco de elección fue el fenobarbital. Conclusiones. El diagnóstico de convulsiones neonatales requiere una alta sospecha clínica y una confirmación electroclínica. La mayoría tiene evolución favorable, pero un porcentaje constituye el inicio de una epilepsia, cuya identificación determinará su manejo terapéutico.