Homologous recombination deficiency (HRD) has become an important prognostic and predictive biomarker for patients with high-grade serous ovarian cancer who may benefit from poly-ADP ribose polymerase inhibitors (PARPi) and platinum-based therapies. HRD testing provides relevant information to personalize patients' treatment options and has been progressively incorporated into diagnostic laboratories. Here, we assessed the performance of an in-house HRD testing system deployable in a diagnostic clinical setting, comparing results from two commercially available next-generation sequencing (NGS)-based tumor tests (SOPHiA DDM HRD Solution and AmoyDx (HRD Focus Panel)) with the reference assay from Myriad MyChoice (CDx).
View Article and Find Full Text PDFObjective: The classic triad, which defines IFAP syndrome, is ichthyosis follicularis, alopecia, and photophobia. It is a rare X-linked genetic disorder characterized by multiple congenital anomalies with variable severity, caused by pathogenic variants in the MBTPS2 gene, which encodes a zinc metalloprotease that is essential for normal development. This study aimed to report a case of a Brazilian patient with IFAP syndrome presenting skeletal anomalies, which is a rare finding among patients from different families.
View Article and Find Full Text PDFWe determined the frequency and mutational spectrum of BRCA1 and BRCA2 in a series of patients at high risk for developing breast cancer from Brazil. A total of 1267 patients were referred for BRCA genetic testing, and no obligation of fulfilling criteria of mutation probability methods for molecular screening was applied. Germline deleterious mutations in BRCA1/2 (i.
View Article and Find Full Text PDFChromosomal microarray analysis (CMA) has been recommended and practiced routinely since 2010 both in the USA and Europe as the first-tier cytogenetic test for patients with unexplained neurodevelopmental delay/intellectual disability, autism spectrum disorders, and/or multiple congenital anomalies. However, in Brazil, the use of CMA is still limited, due to its high cost and complexity in integrating the results from both the private and public health systems. Although Brazil has one of the world's largest single-payer public healthcare systems, nearly all patients referred for CMA come from the private sector, resulting in only a small number of CMA studies in Brazilian cohorts.
View Article and Find Full Text PDFChromosomal microarray analyses (CMA) have greatly increased both the yield and diagnostic accuracy of postnatal analysis; it has been used as a first-tier cytogenetic test in patients with intellectual disability, autism spectrum disorder, and multiple congenital abnormalities. During the last 15 years, we performed CMA in approximately 8,000 patients with neurodevelopmental and/or congenital disorders, of which 13 (0.16%) genetically catastrophic complex chromosomal rearrangements were identified.
View Article and Find Full Text PDFBackground: Numerous publications have reported the incidental detection of occult malignancies upon routine noninvasive prenatal testing (NIPT). However, these studies were not designed to evaluate the NIPT performance for cancer detection.
Methods: We investigated the sensitivity of a genome-wide NIPT pipeline, called GIPSeq, for detecting cancer-specific copy number alterations (CNAs) in plasma tumor DNA (ctDNA) of patients with breast cancer.
Mosaic segmental and whole chromosome copy number alterations are postzygotic variations known to be associated with several disorders. We have previously presented an efficient targeted sequencing approach to simultaneously detect point mutations and copy number variations (CNVs). In this study, we evaluated the efficiency of this approach to detect mosaic CNVs, using seven postnatal and 19 tumor samples, previously characterized by chromosomal microarray analyses (CMA).
View Article and Find Full Text PDFPurpose: Whereas noninvasive prenatal screening for aneuploidies is widely implemented, there is an increasing need for universal approaches for noninvasive prenatal screening for monogenic diseases. Here, we present a cost-effective, generic cell-free fetal DNA (cffDNA) haplotyping approach to scan the fetal genome for the presence of inherited monogenic diseases.
Methods: Families participating in the preimplantation genetic testing for monogenic disorders (PGT-M) program were recruited for this study.
Non-invasive prenatal testing (NIPT) is accurate for fetal sex determination in singleton pregnancies, but its accuracy is not well established in twin pregnancies. Here, we present an accurate sex prediction model to discriminate fetal sex in both dichorionic diamniotic (DCDA) and monochorionic diamniotic/monochorionic monoamniotic (MCDA/MCMA) twin pregnancies. A retrospective analysis was performed using a total of 198 twin pregnancies with documented sex.
View Article and Find Full Text PDFPurpose: Noninvasive prenatal screening (NIPS) using genome sequencing also reveals maternal copy-number variations (CNVs). Those CNVs can be clinically actionable or harmful to the fetus if inherited. CNVs in the DMD gene potentially causing dystrophinopathies are among the most commonly observed maternal CNVs.
View Article and Find Full Text PDFAging is a complex process strongly determined by genetics. Previous reports have shown that the genome of neuronal cells displays somatic genomic mosaicism including DNA copy number variations (CNVs). CNVs represent a significant source of genetic variation in the human genome and have been implicated in several disorders and complex traits, representing a potential mechanism that contributes to neuronal diversity and the etiology of several neurological diseases and provides new insights into the normal, complex functions of the brain.
View Article and Find Full Text PDFWe evaluated an approach to detect copy number variants (CNVs) and single nucleotide changes (SNVs), using a clinically focused exome panel complemented with a backbone and SNP probes that allows for genome-wide copy number changes and copy-neutral absence of heterozygosity (AOH) calls; this approach potentially substitutes the use of chromosomal microarray testing and sequencing into a single test. A panel of 16 DNA samples with known alterations ranging from megabase-scale CNVs to single base modifications were used as positive controls for sequencing data analysis. The DNA panel included CNVs (n = 13) of variable sizes (23 Kb to 27 Mb), uniparental disomy (UPD; n = 1), and single point mutations (n = 2).
View Article and Find Full Text PDFDysregulation of calcium (Ca(2+)) homeostasis is now being recognized to be a key step in the pathogenesis of Alzheimer's disease (AD). Data from the literature, in particular the association between AD and polymorphism that interfere with Ca(2+) homeostasis indicates the presence of genetic factors in this process; further, presenilins mutations, which are known to cause the familial form of AD, are involved in the regulation of intracellular Ca(2+) stores. Here, we wish to draw attention to rare DNA copy number variations identified in two subjects with late-onset AD that led to partial or full duplication of genes that encode different subunits of the same type of voltage-gated Ca(2+) channels; these duplications of voltage-gated Ca(2+) channel genes is consistent with the critical role of calcium signaling in molecular processes underlying memory as has been demonstrated by several studies.
View Article and Find Full Text PDFThis study investigated for the first time the genomewide DNA methylation changes of noncoding RNA genes in the temporal cortex samples from individuals with Alzheimer's disease (AD). The methylome of 10 AD individuals and 10 age-matched controls were obtained using Illumina 450 K methylation array. A total of 2,095 among the 15,258 interrogated noncoding RNA CpG sites presented differential methylation, 161 of which were associated with miRNA genes.
View Article and Find Full Text PDFArgyrophilic grain disease (AGD) is a progressive neurodegenerative disease of the human brain that has never been associated to a particular gene locus. In the present study, we report the results of a CNV investigation in 29 individuals whose anatomopathologic investigation of the brain showed AGD. Rare CNVs were identified in six patients (21%), in particular a 40 kb deletion at 17p13.
View Article and Find Full Text PDFAims: The circadian rhythm in mammalian pineal melatonin secretion is modulated by norepinephrine (NE) released at night. NE interaction with β1-adrenoceptors activates PKA that phosphorylates the transcription factor CREB, leading to the transcription and translation of the arylalkylamine-N-acetyltransferase (AANAT) enzyme. Several studies have reported the interplay between CREB and the nuclear factor-κB (NF-κB) and a circadian rhythm for this transcription factor was recently described in the rat pineal gland.
View Article and Find Full Text PDFThe glutamatergic modulation of melatonin synthesis is well known, along with the importance of astrocytes in mediating glutamatergic signaling in the central nervous system. Pinealocytes and astrocytes are the main cell types in the pineal gland. The objective of this work was to investigate the interactions between astrocytes and pinealocytes as a part of the glutamate inhibitory effect on melatonin synthesis.
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