Although the diurnal fluctuation of motor dysfunction, reversible with small doses of dopamine, is a cornerstone for the phenotype of the autosomal dominant Segawa syndrome, the non-motor symptoms of ...this neurotransmitter deficiency have still received limited attention.
This study aims to evaluate non-motor symptoms of this dopa-responsive dystonia through an intrafamilial comparative cross-sectional study.
Seventeen individuals with a c.IVS5 + 3insT (c.626 + 3insT) variation in the GTP cyclohydrolase-1 gene (GCH1, HGNC: 4193) and 34 intrafamilial controls were studied using the Beck Depression Inventory-II, the Wiener Matrizen Test 2, the Epworth Sleepiness Scale, the Pittsburgh Sleep Quality Index, the MINI/MINI PLUS Questionnaires, the World Health Organization Quality of Life – BREF Instrument and a drug use assessment questionnaire.
No significant difference was found between the groups in the prevalence of sleep disorders and in cognitive function. Nevertheless, generalized anxiety disorder (p = 0.050) and attention-deficit/hyperactivity disorder in childhood (p = 0.011) were observed only in individuals without the molecular variation. The group with the GCH1 variation presented a worse perception about how safe they feel in their daily lives (p = 0.034), less satisfaction with themselves (p = 0.049) and with their relationships (p = 0.029), and a higher prevalence of past major depressive episodes before use of L-Dopa (p = 0.046).
Low dopamine could have been protective against generalized anxiety disorder and attention-deficit/hyperactivity disorder in childhood in Segawa group individuals. The prevalence of depression was higher in individuals with the molecular variant prior to the L-Dopa treatment. Considering it, the penetrance estimates for the variant carriers increased from 58.8% to up to 88% in this large studied family. Additionally, neuropsychiatric tests of all individuals with a molecular diagnosis in an affected family are a valuable instrument for its clinical management.
•Depression can be a non-motor symptom of autosomal dominant DYT/PARK-GCH1.•Variable expressivity and penetrance can be considered high in this syndrome.•Relatives without dystonia should also be investigated for the genetic variation.
Sexual dimorphism in DNA methylation levels is a recurrent epigenetic feature in different human cell types and has been implicated in predisposition to disease, such as psychiatric and autoimmune ...disorders. To elucidate the genetic origins of sex-specific DNA methylation, we examined DNA methylation levels in fibroblast cell lines and blood cells from individuals with different combinations of sex chromosome complements and sex phenotypes focusing on a single autosomal region--the differentially methylated region (DMR) in the promoter of the zona pellucida binding protein 2 (ZPBP2) as a reporter.
Our data show that the presence of the sex determining region Y (SRY) was associated with lower methylation levels, whereas higher X chromosome dosage in the absence of SRY led to an increase in DNA methylation levels at the ZPBP2 DMR. We mapped the X-linked modifier of DNA methylation to the long arm of chromosome X (Xq13-q21) and tested the impact of mutations in the ATRX and RLIM genes, located in this region, on methylation levels. Neither ATRX nor RLIM mutations influenced ZPBP2 methylation in female carriers.
We conclude that sex-specific methylation differences at the autosomal locus result from interaction between a Y-linked factor SRY and at least one X-linked factor that acts in a dose-dependent manner.
Abstract
Mucolipidoses (MLs) II and III are rare lysosomal diseases caused by deficiency of GlcNAc-1-phosphotransferase, and clinical manifestations are multisystemic. Clinical and demographic data ...from 1983 to 2013 were obtained retrospectively. Twenty-seven patients were included (ML II = 15, ML III α/beta = 9, ML III gamma = 3). The median age at diagnosis was 2.7 years. The predominant clinical presentations were skeletal symptoms. The ML II patients showed physical and cognitive impairment, while the ML III α/beta patients have more somatic abnormalities and usually were delayed in early development as compared with ML III gamma patients. This is the most comprehensive study exploring characteristics of Brazilian patients with MLs II and III.
Literature review of new genes related to osteogenesis imperfecta (OI) and update of its classification.
Literature review in the PubMed and OMIM databases, followed by selection of relevant ...references.
In 1979, Sillence et al. developed a classification of OI subtypes based on clinical features and disease severity: OI type I, mild, common, with blue sclera; OI type II, perinatal lethal form; OI type III, severe and progressively deforming, with normal sclera; and OI type IV, moderate severity with normal sclera. Approximately 90% of individuals with OI are heterozygous for mutations in the COL1A1 and COL1A2 genes, with dominant pattern of inheritance or sporadic mutations. After 2006, mutations were identified in the CRTAP, FKBP10, LEPRE1, PLOD2, PPIB, SERPINF1, SERPINH1, SP7, WNT1, BMP1, and TMEM38B genes, associated with recessive OI and mutation in the IFITM5 gene associated with dominant OI. Mutations in PLS3 were recently identified in families with osteoporosis and fractures, with X-linked inheritance pattern. In addition to the genetic complexity of the molecular basis of OI, extensive phenotypic variability resulting from individual loci has also been documented.
Considering the discovery of new genes and limited genotype-phenotype correlation, the use of next-generation sequencing tools has become useful in molecular studies of OI cases. The recommendation of the Nosology Group of the International Society of Skeletal Dysplasias is to maintain the classification of Sillence as the prototypical form, universally accepted to classify the degree of severity in OI, while maintaining it free from direct molecular reference.
Revisão da literatura sobre novos genes relacionados à osteogênese imperfeita (OI) e atualização da sua classificação.
Revisão nas bases de dados do PUBMED e OMIM com seleção de referências relevantes.
Sillence et al., em 1979, desenvolveram uma classificação dos subtipos de OI baseada em características clínicas e gravidade da doença: OI tipo I, forma leve, comum, com escleras azuladas; OI tipo II, forma perinatal letal; OI tipo III, forma grave e progressivamente deformante com esclera normal; e OI tipo IV, forma de gravidade moderada com esclera normal. Cerca de 90% dos indivíduos com OI são heterozigotos para mutações em COL1A1 e COL1A2, com padrão de herança dominante ou esporádico. A partir de 2006 foram identificadas mutações nos genes CRTAP, FKBP10, LEPRE1, PLOD2, PPIB, SERPINF1, SERPINH1, SP7, WNT1, BMP1 e TMEM38B associadas à OI recessiva e mutação em IFITM5 associada à OI dominante. Mutações em PLS3 foram identificadas recentemente em famílias com osteoporose e fraturas, com padrão de herança ligado ao X. Além da complexidade genética das bases moleculares das OI, extensa variabilidade fenotípica resultante de loci individuais também tem sido documentada.
Face à descoberta de novos genes e à correlação genótipo-fenótipo limitada, o uso de ferramentas de sequenciamento de nova geração torna-se útil no estudo molecular de casos de OI. A recomendação do Grupo de Nosologia da Sociedade Internacional de Displasias Esqueléticas é manter a classificação de Sillence como a forma prototípica e universalmente aceita para classificar o grau de gravidade na OI, e libertá-la de referência molecular direta.
Quantitative analysis of amino acids in blood and urine is primarily indicated for the diagnosis of amino acid disorders. The high‐performance liquid chromatography (HPLC) technique is frequently ...used for this detection. The frequency of sample collection on filter paper has been increasing exponentially, and there are many advantages attributed to processing biological samples in this way. The aim of this study was to validate a quantitative analysis of amino acids by HPLC in blood and urine collected on filter paper and to establish reference values in the neonatal period. Dried blood and dried urine samples of respectively 58 and 45 healthy newborns (2–9 days) were collected. Pre‐treatment and extraction of samples were done according to the literature. Separation and analysis of amino acids were carried out by HPLC with fluorescence detection. The developed method demonstrated excellent separation, linearity, limits of detection and quantification, repeatability and recovery. The reference values for 17 amino acids were defined in dried blood and urine samples of newborns. This work presents a simple, fast and effective method for the simultaneous analysis of 17 amino acids in blood and urine collected on filter paper in a single run. The reference values were established and validated.
Abstract The 6p terminal deletions are rare and present variability of clinical features, which increases the importance of reporting additional cases in order to better characterize ...genotype–phenotype correlations. We report a 12-year-old girl with a de novo deletion in 6p25.1-pter characterized by high-resolution karyotyping and FISH. Further analysis using oligonucleotide array-CGH revealed a 5.06 Mb 6p25.1-pter deletion associated with a contiguous 1 Mb 6p25.1 duplication. The patient presented normal growth, developmental delay, frontal bossing, severe hypertelorism, corectopia, wide and depressed nasal bridge, mild learning disability, hearing loss and diffuse leukopathy. Additionaly, she presented peculiar phenotypic features reported herein for the first time in 6p25 deletion syndrome: cerebrospinal fluid fistula and bones resembling those seen in 3-M syndrome. The distinctive phenotype of the 6p25 deletion syndrome has been mainly correlated with the FOXC1 and FOXF2 genes deletions, both related mainly to eye development. We also consider the SERPINB6 as a candidate for sensorineural hearing loss and TUBB2A as a candidate for our patient's skeletal features. In addition, as our patient had a duplication including NRN1 , a gene related with neurodevelopment, synaptic plasticity and cognitive dysfunction in schizophrenia, we suggest that this gene could be associated with her white matter abnormalities and neurocognitive phenotype.
Recombinant human α-
l-iduronidase (Aldurazyme
®, laronidase) is approved as an enzyme replacement therapy to treat the lysosomal storage disorder, mucopolysaccharidosis type I (MPS I) at a dose of ...0.58
mg/kg by once-weekly intravenous infusion. To assess whether alternate dosing regimens might provide a better reduction in lysosomal storage, a 26-week, randomized, open-label, multinational dose-optimization trial was conducted. The pharmacodynamic effect and safety of the approved laronidase dose was compared to three alternative regimens (1.2
mg/kg every 2 weeks; 1.2
mg/kg every week; 1.8
mg/kg every 2 weeks) among 33 MPS I patients. The four treatment regimens showed no significant differences in the reduction of urinary glycosaminoglycan excretion or liver volume. Laronidase had an acceptable safety profile in all dose regimen groups. Infusion-associated reactions were the most common drug-related adverse events across dose regimens (by patient incidence), and included pyrexia (21%), vomiting (15%), rash (15%), and urticaria (12%). Patients in the approved dose group had the lowest incidence of drug-related adverse events (38% vs. 63–75%) and infusion-associated reactions (25% vs. 25–63%). There was one death: a patient with acute bronchitis died of respiratory failure 6
h after completing the first laronidase infusion. The approved 0.58
mg/kg/week laronidase dose regimen provided near-maximal reductions in glycosaminoglycan storage and the best benefit-to-risk ratio. The 1.2
mg/kg every 2 weeks regimen may be an acceptable alternative for patients with difficulty receiving weekly infusions, but the long-term effects of this regimen are unknown.
α/β-hydrolase domain-containing protein 5 (ABHD5) plays an important role in the triacylglycerols (TAG) hydrolysis. Indeed, ABHD5 is the co-activator of adipose triglyceride lipase (ATGL), that ...catalyses the initial step of TAG hydrolysis. Mutations in ABHD5 gene are associated with the onset of Chanarin-Dorfman syndrome (CDS), a rare autosomal recessive lipid storage disorder, characterized by non-bullous congenital ichthyosiform erythroderma (NCIE), hepatomegaly and liver steatosis.
We describe here a 5-years-old Brazilian child who presented with NCIE at birth and diffuse micro and macro-vesicular steatosis on liver biopsy since she was 2 years old. Molecular analysis of coding sequence and putative 5' regulatory region of ABHD5 gene was performed. A homozygous novel deletion, affecting the promoter region and the exon 1, was identified, confirming the suspected diagnosis of CDS for this patient. RT-PCR analysis showed that the genomic rearrangement completely abolished the ABHD5 gene expression in the patient, while only a partial loss of expression was detected in her parents. This is the first report describing the identification of a large deletion encompassing the promoter region of ABHD5 gene. The total loss of ABHD5 expression may explain the early onset of CDS and the severe liver involvement. After molecular diagnosis, the patient started a special diet, poor in fatty acids with medium chain triglycerides (MCT), and showed hepatic and dermatologic improvement in spite of severe molecular defect.
This case report extends the spectrum of disease-causing ABHD5 mutations in CDS providing evidence for a novel pathogenic mechanism for this rare disorder. Moreover, our preliminary data show that early diagnosis and prompt treatment of neutral lipid accumulation might be useful for CD patients.
Chitotriosidase (ChT) is a human chitinase secreted by activated macrophages and its activity is used in therapeutic monitoring of Gaucher disease (GD), the most common lysosomal storage disease. ...About 6% of the population is homozygous for a duplication of 24 bp in exon 11 of the CHIT1 gene (dup24), which is the main polymorphism that results in the absence of ChT. As ChT enzyme activity can be used as a biomarker in GD, it is important to know the CHIT1 genotype of each patient. In this study, ChT activity and CHIT1 genotype were evaluated in 33 GD type 1 patients under treatment in the state of Minas Gerais, Brazil, and compared to healthy controls. As expected, the enzyme activity was found to be higher in GD type 1 patients than in healthy subjects. Four patients had no ChT activity. Their genotype revealed three patients (9%) homozygous for dup24 allele and one patient with two polymorphisms in exon 11: G354R and a 4 bp deletion at the exon-intron 11 boundary (g.16993_16996delGAGT), the later described for the first time in literature. Two other patients with lower ChT activity presented a polymorphism in exon 4 (c.304G>A, p.G102S), without dup24 allele. In conclusion, this study demonstrated that ChT activity can be used for therapeutic monitoring in 82% of GD patients of the state of Minas Gerais, Brazil.
ABSTRACT Introduction: The high performance liquid chromatography is a technique used for quantification of amino acids in plasma. The definition of reference intervals in the population is very ...important for the diagnosis and monitoring of individuals with amino acid disorders. Objectives: The objectives of this study were to validate a method for amino acids quantification and define reference intervals in Brazilian children. Results: Good chromatographic separation was achieved using C18 solid-core column. The method showed satisfactory linearity, limits of detection and quantification, precision and accuracy. The reference ranges for aspartate, glutamate, asparagine, histidine, serine, glutamine, arginine, tyrosine, alanine, tryptophan, methionine, valine, phenylalanine, isoleucine and leucine were defined in a group of 60 healthy individuals aged 2 to 14 years. Conclusion: The presented technique can be applied in clinical practice. Each laboratory should preferably establish its own reference intervals. If that is not possible, it is recommended the use of the reference intervals described in this study for the diagnosis and monitoring of Brazilian children in this age group.