Rare Variants in 48 Genes Account for 42% of Cases of Epilepsy With or Without Neurodevelopmental Delay in 246 Pediatric Patients.

In order to characterize the genetic architecture of epilepsy in a pediatric population from the Iberian Peninsula (including the Canary Islands), we conducted targeted exome sequencing of 246 patients with infantile-onset seizures with or without neurodevelopmental delay. We detected 107 variants in 48 different genes, which were implicated in neuronal excitability, neurodevelopment, synaptic transmission, and metabolic pathways. In 104 cases (42%) we detected variant(s) that we classified as pathogenic or likely pathogenic.

Evolution of tyrosinemia type 1 disease in patients treated with nitisinone in Spain.

Treatment with nitisinone (NTBC) has brought about a drastic improvement in the treatment and prognosis of hereditary tyrosinemia type I (HT1). We conducted a retrospective observational multicentric study in Spanish HT1 patients treated with NTBC to assess clinical and biochemical long-term evolution.We evaluated 52 patients, 7 adults and 45 children, treated with NTBC considering: age at diagnosis, diagnosis by clinical symptoms, or by newborn screening (NBS); phenotype (acute/subacute/chronic), mutational analysis; symptoms at diagnosis and clinical course; biochemical markers; doses of NTBC; treatment adherence; anthropometric evolution; and neurocognitive outcome.

PattRec: An easy-to-use CNV detection tool optimized for targeted NGS assays with diagnostic purposes.

Genetic laboratories use custom-commercial targeted next-generation sequencing (tg-NGS) assays to identify disease-causing variants. Although the high coverage achieved with these tests allows for the detection of copy number variants (CNVs), which account for an important proportion of the genetic burden in human diseases, an easy-to-use tool for automatic CNV detection is still lacking. This article presents a new CNV detection tool optimized for tg-NGS data: PattRec.

Free-access copy-number variant detection tools for targeted next-generation sequencing data.

Copy number variants (CNVs) are intermediate-scale structural variants containing copy number changes involving DNA fragments of between 1 kb and 5 Mb. Although known to account for a significant proportion of the genetic burden in human disease, the role of CNVs (especially small CNVs) is often underestimated, as they are undetectable by traditional Sanger sequencing. Since the development of next-generation sequencing (NGS) technologies, several research groups have compared depth of coverage (DoC) patterns between samples, an approach that may facilitate effective CNV detection.

Retrospective study to identify risk factors for chronic kidney disease in children with congenital solitary functioning kidney detected by neonatal renal ultrasound screening.

To evaluate the prognostic significance of factors frequently associated with a reduction in renal mass, such as prematurity, low birth weight, and congenital anomalies of kidney and urinary tract (CAKUT), in patients with solitary functioning kidney (SFK) and investigate signs of early renal injury due to glomerular hyperfiltration damage or dysplasia in the remaining kidney.Retrospective observational study of congenital SFK diagnosed and followed at a tertiary care hospital over a period of 10 years in which 32,900 newborns underwent routine neonatal abdominal ultrasound screening. We analyzed age at diagnosis, sex, gestational age, anthropometric measurements at birth and prenatal and neonatal ultrasound findings, in addition to follow-up data corresponding to imaging findings (ultrasound, micturating cystourethrography, dimercaptosuccinic acid renal, and scintigraphy), ipsilateral CAKUT, compensatory hypertrophy, and renal injury in the form of albuminuria, blood pressure, and estimated glomerular filtration rate (eGFR).

Carbohydrate status in patients with phenylketonuria.

Background: In patients with phenylketonuria (PKU), a low-phenylalanine (Phe) diet supplemented with low-protein foods and a Phe-free amino acid mixture favors a dietary intake rich in carbohydrates, but little is known about how these molecules are metabolized in this setting. The objective of the present study was to analyze carbohydrate metabolism in patients with hyperphenylalaninemia.

Methods: We conducted a multicenter cross-sectional study to investigate biochemical markers of basal and postprandial carbohydrate metabolism in PKU patients according to age, Phe tolerance, waist circumference and body mass index (BMI), diet, tetrahydrobiopterin (BH4) supplementation, and adherence to treatment.

Prioritization of Variants Detected by Next Generation Sequencing According to the Mutation Tolerance and Mutational Architecture of the Corresponding Genes.

The biggest challenge geneticists face when applying next-generation sequencing technology to the diagnosis of rare diseases is determining which rare variants, from the dozens or hundreds detected, are potentially implicated in the patient's phenotype. Thus, variant prioritization is an essential step in the process of rare disease diagnosis. In addition to conducting the usual in-silico analyses to predict variant pathogenicity (based on nucleotide/amino-acid conservation and the differences between the physicochemical features of the amino-acid change), three important concepts should be borne in mind.

A novel missense mutation in GRIN2A causes a nonepileptic neurodevelopmental disorder.

Background: Mutations in the GRIN2A gene, which encodes the GluN2A (glutamate [NMDA] receptor subunit epsilon-1) subunit of the N-methyl-d-aspartate receptor, have been identified in patients with epilepsy-aphasia spectrum disorders, idiopathic focal epilepsies with centrotemporal spikes, and epileptic encephalopathies with severe developmental delay. However, thus far, mutations in this gene have not been associated with a nonepileptic neurodevelopmental disorder with dystonia.

Objectives: The objective of this study was to identify the disease-causing gene in 2 siblings with neurodevelopmental and movement disorders with no epileptiform abnormalities.

Arterial stiffness assessment in patients with phenylketonuria.

In patients with phenylketonuria (PKU) compliant to diet greater tendency to overweight and higher inflammatory biomarkers levels than controls were reported. Although this could lead to atherogenesis, the elastic properties of large arteries in PKU patients have never been assessed. The aim of this study was to assess arterial stiffness measured by applanation tonometry in PKU patients compared to healthy controls.

Similarities between acylcarnitine profiles in large for gestational age newborns and obesity.

Large for gestational age (LGA) newborns have an increased risk of obesity, insulin resistance, and metabolic syndrome. Acylcarnitine profiles in obese children and adults are characterized by increased levels of C3, C5, and certain medium-chain (C12) and long-chain (C14:1 and C16) acylcarnitines. C2 is also increased in insulin-resistant states.

Molecular-genetic characterization and rescue of a TSFM mutation causing childhood-onset ataxia and nonobstructive cardiomyopathy.

Oxidative phosphorylation dysfunction has been found in many different disorders. This biochemical pathway depends on mitochondrial protein synthesis. Thus, mutations in components of the mitochondrial translation system can be responsible for some of these pathologies.

Lipid profile status and other related factors in patients with Hyperphenylalaninaemia.

Background: The mainstay of treating patients with phenylketonuria (PKU) is based on a Phe-restricted diet, restrictive in natural protein combined with Phe-free L-amino acid supplements and low protein foods. This PKU diet seems to reduce atherogenesis and confer protection against cardiovascular diseases but the results from the few published studies have been inconclusive. The aim of our study was to evaluate the relationship between the lipid profile and several treatment-related risk factors in patients with hyperphenylalaninaemia (HPA) in order to optimize their monitoring.

Micronutrient in hyperphenylalaninemia.

The data presented here are the biochemical parameters of 156 patients with hyperphenylalaninemia. PKU patients, who, in order to maintain optimal serum Phe concentrations, receive dietary treatment consisting of a diet low in natural protein supplemented with special low protein foods and a Phe-free amino acid mixture, vitamins and minerals. The obtained data reflects a high percentage of patients with prealbumin and selenium deficiencies, as well as an increased level of folic acid.

Vitamin and mineral status in patients with hyperphenylalaninemia.

Natural sources of protein and some vitamins and minerals are limited in phenylketonuria (PKU) treated patients, who should receive optimal supplementation although this is not yet fully established. We conducted a cross-sectional observational multicenter study including 156 patients with hyperphenylalaninemia. Patients were stratified by age, phenotype, disease detection and type of treatment.