Sci Rep
February 2024
Chromosomal microarray (CMA) is the reference in evaluation of copy number variations (CNVs) in individuals with neurodevelopmental disorders (NDDs), such as intellectual disability (ID) and/or autism spectrum disorder (ASD), which affect around 3-4% of the world's population. Modern platforms for CMA, also include probes for single nucleotide polymorphisms (SNPs) that detect homozygous regions in the genome, such as long contiguous stretches of homozygosity (LCSH). These regions result from complete or segmental chromosomal homozygosis and may be indicative of uniparental disomy (UPD), inbreeding, population characteristics, as well as replicative DNA repair events.
View Article and Find Full Text PDFThis study aimed to assess the Family Quality of Life (FQoL) of Brazilian families with male children with Fragile X syndrome (FXS). Data from 53 families were collected using forms that included sociodemographic and clinical information, as well as the Beach Center Family Quality of Life Scale, a 5-point Likert scale ranging from "very dissatisfied" (1) to "very satisfied" (5). The mean overall FQoL score was 3.
View Article and Find Full Text PDFObjective: Our study aimed to identify mutations in the FMR1 gene in a group of Brazilian women diagnosed with primary ovarian insufficiency (POI).
Methods: This cross-sectional study included patients aged under 40 years with confirmed POI from a convenience sample of patients seen from June 2017 to December 2018 at a University Hospital in Curitiba, Brazil. Genomic DNA was extracted and analyzed using FragilEase(tm) PCR kits (PerkinElmer), a commercially available test that enables the quantification of CGG trinucleotide repeat expansions in the FMR1 gene.
Background: Intellectual Disability (ID) is characterized by significant limitations that affect intellectual functioning, adaptive behavior, and practical skills which directly interfere with interpersonal relationships and the environment. In Western countries, individuals with ID are overrepresented in the health system, often due to associated comorbidities, and its life-time cost places ID as one of the most expensive conditions of all diagnoses in the International Classification of Diseases. Most of the people affected (75%) live in low-income countries, suffer from malnutrition, lack health care, and do not have access to adequate treatment.
View Article and Find Full Text PDFObjectives: Fragile X syndrome (FXS) is caused by expansion of the number of cytosine-guanine-guanine (CGG) repeats in the regulatory region of the gene (. The molecular diagnoses of FXS can be performed using two tests based on two different techniques, namely polymerase chain reaction (PCR) and Southern blotting (SB). However, both of these techniques have limitations.
View Article and Find Full Text PDFChromosomal microarray (CMA) is now recommended as first tier for the evaluation in individuals with unexplained neurodevelopmental disorders (ND). However, in developing countries such as Brazil, classical cytogenetic tests are still the most used in clinical practice, as reflected by the scarcity of publications of microarray investigation in larger cohorts. This is a retrospective study which analyses the reading files of CMA and available clinical data from 420 patients from the south of Brazil, mostly children, with neurodevelopmental disorders requested by medical geneticists and neurologists for diagnostic purpose.
View Article and Find Full Text PDFBMC Med Genomics
March 2019
Background: Currently, chromosomal microarrays (CMA) are recommended as first-tier test in the investigation of developmental disorders to examine copy number variations. The modern platforms also include probes for single nucleotide polymorphisms (SNPs) that detect homozygous regions in the genome, such as long contiguous stretches of homozygosity (LCSH) also named runs of homozygosity (ROH). LCHS are chromosomal segments resulting from complete or segmental chromosomal homozygosity, which may be indicative of uniparental disomy (UPD), consanguinity, as well as replicative DNA repair events, however also are common findings in normal populations.
View Article and Find Full Text PDFMental retardation (MR) is a definition which comprises a series of conditions whose common feature is an intellectual handicap that develops before the age of 18, afflicting 2-3% of the world's population. The classification of MR into different categories is determined by the extent of the handicap instead of its cause, which often remains unrecognized. Sometimes, MR runs in a family, characterizing familial MR, and those cases permit an in-depth look into the genetic causes and consequences of the problem.
View Article and Find Full Text PDFAutism, which is common in individuals with fragile X syndrome, is often difficult to diagnose. We compared the diagnostic classifications of two measures for autism diagnosis, the ADOS and the ADI-R, in addition to the DSM-IV-TR in 63 males with this syndrome. Overall, 30% of the subjects met criteria for autistic disorder and 30% met criteria for PDD-NOS.
View Article and Find Full Text PDFAm J Med Genet B Neuropsychiatr Genet
November 2005
Until recently, individuals with premutation alleles (55-200 CGG repeats) of the fragile X mental retardation 1 (FMR1) gene were believed to be psychologically unaffected. However, the recent documentation of abnormal elevation of FMR1 mRNA, discovery of fragile X-associated tremor/ataxia syndrome (FXTAS), and reports of psychiatric disorders in children and adults with the premutation have suggested a pathogenic gene-brain-behavior mechanism. In a large collaborative study, 68 men and 144 women with the FMR1 premutation completed a psychological symptoms checklist and FMR1 genetic testing, including determination of CGG repeat size, percentage of FMR1 protein (FMRP)-positive lymphocytes, and FMR1 mRNA levels.
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