Repository logo
 

Artigos publicados em revistas indexadas na Pubmed/Medline

Permanent URI for this collection

Browse

Recent Submissions

Now showing 1 - 10 of 29
  • Case Report: Diffuse Polymicrogyria Associated With a Novel ADGRG1 Variant
    Publication . Carneiro, Fábio; Duarte, Júlia; Laranjeira, Francisco; Barbosa-Gouveia, Sofia; Couce, María-Luz; Fonseca, Maria José
    Pathogenic variants of the ADGRG1 gene are associated with bilateral frontoparietal polymicrogyria, defined radiologically by polymicrogyria with an anterior-posterior gradient, pontine and cerebellar hypoplasia and patchy white matter abnormalities. We report a novel homozygous ADGRG1 variant with atypical features. The patient presented at 8 months of age with motor delay, esotropia, hypotonia with hyporeflexia and subsequently developed refractory epilepsy. At the last assessment, aged 12 years, head control, sitting and language were not acquired. Magnetic resonance imaging revealed diffuse polymicrogyria with relative sparing of the anterior temporal lobes, without an anterior-posterior gradient, diffuse hypomyelination and pontine and cerebellar hypoplasia. A panel targeting brain morphogenesis defects yielded an unreported homozygous ADGRG1 nonsense variant (dbSNP rs746634404), present in the heterozygous state in both parents. We report a novel ADGRG1 variant associated with diffuse polymicrogyria without an identifiable anterior-posterior gradient, diffuse hypomyelination and a severe motor and cognitive phenotype. Our case highlights the phenotypic diversity of ADGRG1 pathogenic variants and the clinico-anatomical overlap between recognized polymicrogyria syndromes.
  • International consensus guidelines for phosphoglucomutase 1 deficiency (PGM1‐CDG): Diagnosis, follow‐up, and management
    Publication . Altassan, Ruqaiah; Radenkovic, Silvia; Edmondson, Andrew C.; Barone, Rita; Brasil, Sandra; Cechova, Anna; Coman, David; Donoghue, Sarah; Falkenstein, Kristina; Ferreira, Vanessa; Ferreira, Carlos; Fiumara, Agata; Francisco, Rita; Freeze, Hudson; Grunewald, Stephanie; Honzik, Tomas; Jaeken, Jaak; Krasnewich, Donna; Lam, Christina; Lee, Joy; Lefeber, Dirk; Marques‐da‐Silva, Dorinda; Pascoal, Carlota; Quelhas, D; Raymond, Kimiyo M.; Rymen, Daisy; Seroczynska, Malgorzata; Serrano, Mercedes; Sykut‐Cegielska, Jolanta; Thiel, Christian; Tort, Frederic; Vals, Mari‐Anne; Videira, Paula; Voermans, Nicol; Witters, Peter; Morava, Eva
    Phosphoglucomutase 1 (PGM1) deficiency is a rare genetic disorder that affects glycogen metabolism, glycolysis, and protein glycosylation. Previously known as GSD XIV, it was recently reclassified as a congenital disorder of glycosylation, PGM1-CDG. PGM1-CDG usually manifests as a multisystem disease. Most patients present as infants with cleft palate, liver function abnormalities and hypoglycemia, but some patients present in adulthood with isolated muscle involvement. Some patients develop life-threatening cardiomyopathy. Unlike most other CDG, PGM1-CDG has an effective treatment option, d-galactose, which has been shown to improve many of the patients' symptoms. Therefore, early diagnosis and initiation of treatment for PGM1-CDG patients are crucial decisions. In this article, our group of international experts suggests diagnostic, follow-up, and management guidelines for PGM1-CDG. These guidelines are based on the best available evidence-based data and experts' opinions aiming to provide a practical resource for health care providers to facilitate successful diagnosis and optimal management of PGM1-CDG patients.
  • Development and Validation of a Mathematical Model to Predict the Complexity of FMR1 Allele Combinations
    Publication . Rodrigues, Bárbara; Vale-Fernandes, Emídio; Maia, N; Santos, Flávia; Marques, Isabel; Santos, Rosário; Nogueira, António J. A.; Jorge, Paula
    The polymorphic trinucleotide repetitive region in the FMR1 gene 5'UTR contains AGG interspersions, particularly in normal-sized alleles (CGG < 45). In this range repetitive stretches are typically interrupted once or twice, although alleles without or with three or more AGG interspersions can also be observed. AGG interspersions together with the total length of the repetitive region confer stability and hinder expansion to pathogenic ranges: either premutation (55 < CGG < 200) or full mutation (CGG > 200). The AGG interspersions have long been identified as one of the most important features of FMR1 repeat stability, being particularly important to determine expansion risk estimates in female premutation carriers. We sought to compute the combined AGG interspersion numbers and patterns, aiming to define FMR1 repetitive tract complexity combinations. A mathematical model, the first to compute this cumulative effect, was developed and validated using data from 131 young and healthy females. Plotting of their allelic complexity enabled the identification of two statistically distinct groups - equivalent and dissimilar allelic combinations. The outcome, a numerical parameter designated allelic score, depicts the repeat substructure of each allele, measuring the allelic complexity of the FMR1 gene including the AGGs burden, thus allowing new behavioral scrutiny of normal-sized alleles in females.
  • EMQN best practice guidelines for genetic testing in dystrophinopathies
    Publication . Fratter, Carl; Dalgleish, Raymond; Allen, Stephanie K.; Santos, Rosário; Abbs, Stephen; Tuffery-Giraud, Sylvie; Ferlini, Alessandra
    Dystrophinopathies are X-linked diseases, including Duchenne muscular dystrophy and Becker muscular dystrophy, due to DMD gene variants. In recent years, the application of new genetic technologies and the availability of new personalised drugs have influenced diagnostic genetic testing for dystrophinopathies. Therefore, these European best practice guidelines for genetic testing in dystrophinopathies have been produced to update previous guidelines published in 2010.These guidelines summarise current recommended technologies and methodologies for analysis of the DMD gene, including testing for deletions and duplications of one or more exons, small variant detection and RNA analysis. Genetic testing strategies for diagnosis, carrier testing and prenatal diagnosis (including non-invasive prenatal diagnosis) are then outlined. Guidelines for sequence variant annotation and interpretation are provided, followed by recommendations for reporting results of all categories of testing. Finally, atypical findings (such as non-contiguous deletions and dual DMD variants), implications for personalised medicine and clinical trials and incidental findings (identification of DMD gene variants in patients where a clinical diagnosis of dystrophinopathy has not been considered or suspected) are discussed.
  • Usher syndrome and Nebulin‐associated myopathy in a single patient due to variants in MYO7A and NEB
    Publication . Maia, N; Soares, Ana Rita; Fortuna, Ana; Marques, Isabel; Gonçalves, Ana; Santos, Rosário; Pires, Manuel; De Brouwer, Arjan; Jorge, Paula
    In a patient with Usher syndrome and atypical muscle complaints, we have identified two separate variants in MYO7A andNEB genes by exome sequencing. The homozygous variants in these two recessive genes could explain the full phenotype of our patient.
  • Glycomacropeptide: long-term use and impact on blood phenylalanine, growth and nutritional status in children with PKU
    Publication . Daly, A; Evans, S; Chahal, S; Santra, S; Pinto, A; Jackson, R; Gingell, C; Rocha, Júlio César; Van Spronsen, F J; MacDonald, A
    In phenylketonuria, casein glycomacropeptide (CGMP) requires modification with the addition of some essential and semi essential amino acids to ensure suitability as a protein substitute. The optimal amount and ratio of additional amino acids is undefined. Aim: A longitudinal, parallel, controlled study over 12 months evaluating a CGMP (CGMP-AA2) formulation compared with phenylalanine-free L-amino acid supplements (L-AA) on blood Phe, Tyr, Phe:Tyr ratio, biochemical nutritional status and growth in children with PKU. The CGMP-AA2 contained 36 mg Phe per 20 g protein equivalent. Methods: Children with PKU, with a median age of 9.2 y (5-16y) were divided into 2 groups: 29 were given CGMP-AA2, 19 remained on Phe-free L-AA. The CGMP-AA2 formula gradually replaced L-AA, providing blood Phe concentrations were maintained within target range. Median blood Phe, Tyr, Phe:Tyr ratio and anthropometry, were compared within and between the two groups at baseline, 26 and 52 weeks. Nutritional biochemistry was studied at baseline and 26 weeks only. Results: At the end of 52 weeks only 48% of subjects were able to completely use CGMP-AA2 as their single source of protein substitute. At 52 weeks CGMP-AA2 provided a median of 75% (30-100) of the total protein substitute with the remainder being given as L-AA. Within the CGMP-AA2 group, blood Phe increased significantly between baseline and 52 weeks: [baseline to 26 weeks; baseline Phe 270 μmol/L (170-430); 26 weeks, Phe 300 μmol/L (125-485) p = 0.06; baseline to 52 weeks: baseline, Phe 270 μmol/L (170-430), 52 weeks Phe 300 μmol/L (200-490), p < 0.001)]. However, there were no differences between the CGMP-AA2 and L-AA group for Phe, Tyr, Phe:Tyr ratio or anthropometry at any of the three measured time points. Within the CGMP-AA2 group only weight (p = 0.0001) and BMI z scores (p = 0.0001) increased significantly between baseline to 52 weeks. Whole blood and plasma selenium were significantly higher (whole blood selenium [p = 0.0002]; plasma selenium [p = 0.0007]) at 26 weeks in the CGMP-AA2 group compared L-AA. No differences were observed within the L-AA group for any of the nutritional markers. Conclusions: CGMP-AA increases blood Phe concentrations and so it can only be used partly to contribute to protein substitute in some children with PKU. CGMP-AA should be carefully introduced in children with PKU and close monitoring of blood Phe control is essential.
  • Genomic imbalances defining novel intellectual disability associated loci
    Publication . Lopes, Fátima; Torres, Fátima; Soares, Gabriela; Barbosa, Mafalda; Silva, João; Duque, Frederico; Rocha, Miguel; Sá, Joaquim; Oliveira, Guiomar; Sá, Maria João; Temudo, Teresa; Sousa, Susana; Marques, Carla; Lopes, Sofia; Gomes, Catarina; Barros, Gisela; Jorge, Arminda; Rocha, Felisbela; Martins, Cecília; Mesquita, Sandra; Loureiro, Susana; Cardoso, Elisa Maria; Cálix, Maria José; Dias, Andreia; Martins, Cristina; Mota, Céu R; Antunes, Diana; Dupont, Juliette; Figueiredo, Sara; Figueiroa, Sónia; Gama-de-Sousa, Susana; Cruz, Sara; Sampaio, Adriana; Eijk, Paul; Weiss, Marjan M; Ylstra, Bauke; Rendeiro, Paula; Tavares, Purificação; Reis-Lima, Margarida; Pinto-Basto, Jorge; Fortuna, Ana Maria; Maciel, Patrícia
    Background: High resolution genome-wide copy number analysis, routinely used in clinical diagnosis for several years, retrieves new and extremely rare copy number variations (CNVs) that provide novel candidate genes contributing to disease etiology. The aim of this work was to identify novel genetic causes of neurodevelopmental disease, inferred from CNVs detected by array comparative hybridization (aCGH), in a cohort of 325 Portuguese patients with intellectual disability (ID). Results: We have detected CNVs in 30.1% of the patients, of which 5.2% corresponded to novel likely pathogenic CNVs. For these 11 rare CNVs (which encompass novel ID candidate genes), we identified those most likely to be relevant, and established genotype-phenotype correlations based on detailed clinical assessment. In the case of duplications, we performed expression analysis to assess the impact of the rearrangement. Interestingly, these novel candidate genes belong to known ID-related pathways. Within the 8% of patients with CNVs in known pathogenic loci, the majority had a clinical presentation fitting the phenotype(s) described in the literature, with a few interesting exceptions that are discussed. Conclusions: Identification of such rare CNVs (some of which reported for the first time in ID patients/families) contributes to our understanding of the etiology of ID and for the ever-improving diagnosis of this group of patients.
  • Over Restriction of Dietary Protein Allowance: The Importance of Ongoing Reassessment of Natural Protein Tolerance in Phenylketonuria
    Publication . Pinto, Alex; Almeida, Manuela Ferreira; MacDonald, Anita; Ramos, Paula Cristina; Rocha, Sara; Guimas, Arlindo; Ribeiro, Rosa; Martins, Esmeralda; Bandeira, Anabela; Jackson, Richard; van Spronsen, Francjan; Payne, Anne; Rocha, Júlio César
    Phenylalanine (Phe) tolerance is highly variable in phenylketonuria (PKU) and rarely described in patients aged ≥12 years. Patients ≥12 years of age with PKU were systematically challenged with additional natural protein (NP) if blood Phe levels remained below 480 µmol/L (i.e., upper target blood Phe level for patients aged ≥12 years using Portuguese PKU guidelines). In PKU patients, NP tolerance was calculated at baseline and a median of 6 months after systematic challenge with NP whilst patients were maintaining a blood Phe ≤480 μmol/L. Anthropometry was assessed at both times. Routine blood Phe levels were collected. We studied 40 well-controlled PKU patients (10 hyperphenylalaninemia (HPA), 23 mild and 7 classic PKU), on a low-Phe diet with a mean age of 17 years (12-29 years). Median daily NP intake significantly increased between assessments (35 vs. 40 g/day, p = 0.01). Twenty-six patients (65%) were able to increase their median NP intake by a median 12 g/day (2-42 g)/day and still maintain blood Phe within target range. Out of the previous 26 patients, 20 (77%) (8 HPA, 11 mild and 1 classical PKU) increased NP from animal sources (e.g. dairy products, fish and meat) and 6 patients (23%) (3 mild and 3 classical PKU) from plant foods (bread, pasta, potatoes). Median protein equivalent intake from Phe-free/low-Phe protein substitute decreased (0.82 vs. 0.75 g/kg, p = 0.01), while median blood Phe levels remained unchanged (279 vs. 288 μmol/L, p = 0.06). Almost two-thirds of patients with PKU tolerated additional NP when challenged and still maintained blood Phe within the national target range. This suggests that some patients with PKU treated by a low-Phe diet only may over restrict their NP intake. In order to minimise the burden of treatment and optimise NP intake, it is important to challenge with additional NP at periodic intervals.
  • The Effect of Glycomacropeptide versus Amino Acids on Phenylalanine and Tyrosine Variability over 24 Hours in Children with PKU: A Randomized Controlled Trial
    Publication . Daly, Anne; Evans, Sharon; Chahal, Satnam; Santra, Saikat; Pinto, Alex; Gingell, Cerys; Rocha, Júlio César; van Spronsen, Francjan; Jackson, Richard; MacDonald, Anita
    Introduction: In phenylketonuria (PKU), evidence suggests that casein glycomacropeptide supplemented with rate-limiting amino acids (CGMP-AA) is associated with better protein utilisation and less blood phenylalanine (Phe) variability. Aim: To study the impact of CGMP-AA on blood Phe variability using 3 different dietary regimens in children with PKU. Methods: This was a 6-week randomised controlled cross-over study comparing CGMP-AA vs. Phe-free l-amino acids (l-AA) assessing blood Phe and tyrosine (Tyr) variability over 24 h in 19 children (7 boys) with PKU, with a median age of 10 years (6⁻16). Subjects were randomised to 3 dietary regimens: (1) R1, CGMP-AA and usual dietary Phe (CGMP + Phe); (2) R2, CGMP-AA - Phe content of CGMP-AA from usual diet (CGMP - Phe); and (3) R3, l-AA and usual dietary Phe. Each regimen was administered for 14 days. Over the last 48 h on days 13 and 14, blood spots were collected every 4 h at 08 h, 12 h, 16 h, 20 h, 24 h, and 04 h. Isocaloric intake and the same meal plan and protein substitute dosage at standardised times were maintained when blood spots were collected. Results: Eighteen children completed the study. Median Phe concentrations over 24 h for each group were (range) R1, 290 (30⁻580), R2, 220 (10⁻670), R3, 165 (10⁻640) μmol/L. R1 vs. R2 and R1 vs. R3 p < 0.0001; R2 vs. R3 p = 0.0009. There was a significant difference in median Phe at each time point between R1 vs. R2, p = 0.0027 and R1 vs. R3, p < 0.0001, but not between any time points for R2 vs. R3. Tyr was significantly higher in both R1 and R2 [70 (20⁻240 μmol/L] compared to R3 [60 (10⁻200) μmol/L]. In children < 12 years, blood Phe remained in the target range (120⁻360 μmol/L), over 24 h, for 75% of the time in R1, 72% in R2 and 64% in R3; for children aged ≥ 12 years, blood Phe was in target range (120⁻600 μmol/L) in R1 and R2 for 100% of the time, but 64% in R3. Conclusions: The residual Phe in CGMP-AA increased blood Phe concentration in children. CGMP-AA appears to give less blood Phe variability compared to l-AA, but this effect may be masked by the increased blood Phe concentrations associated with its Phe contribution. Reducing dietary Phe intake to compensate for CGMP-AA Phe content may help.