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ABSTRACT Objective Type 1 diabetes mellitus (T1DM) is an autoimmune disorder caused by a complex interaction between environmental and genetic risk factors. BTB domain and CNC homolog 2 (BACH2) gene encodes a transcription factor that acts on the differentiation and formation of B and T lymphocytes. BACH2 is also involved in the suppression of apoptosis and inflammation in pancreatic beta-cells, indicating a role for it in the development of T1DM. Therefore, the aim of this study was to evaluate the association of the BACH2 rs11755527 single nucleotide polymorphism (SNP) with T1DM. Subjects and methods This case-control study comprised 475 patients with T1DM and 598 nondiabetic individuals. The BACH2 rs11755527 (C/G) SNP was genotyped using real-time PCR with TaqMan MGB probes. Results Genotype distributions of rs11755527 SNP were in accordance with frequencies predicted by the Hardy–Weinberg equilibrium in case and control groups and were similar between groups (P = 0.729). The minor allele frequency was 43.6% in cases and 42.5% in controls (P = 0.604). Moreover, the G allele frequency did not differ between groups when considering different inheritance models and adjusting for age, gender, body mass index, and HLA DR/DQ genotypes of high-risk for T1DM. Although, well-known high-risk T1DM HLA DR/DQ genotypes were associated with T1DM in our population [OR= 7.42 (95% CI 3.34 – 17.0)], this association was not influenced by the rs11755527 SNP. Conclusion The BACH2 rs11755527 SNP seems not to be associated with T1DM in a Brazilian population.

ABSTRACT Chronic myeloid leukemia (CML) is the most common myeloproliferative disorder among chronic neoplasms. The history of this disease joins with the development of cytogenetic analysis techniques in human. CML was the first cancer to be associated with a recurrent chromosomal alteration, a reciprocal translocation between the long arms of chromosomes 9 and 22 - Philadelphia chromosome. This work is an updated review on CML, which highlights the importance of cytogenetics analysis in the continuous monitoring and therapeutic orientation of this disease. The search for scientific articles was carried out in the PubMed electronic database, using the descriptors "leukemia", "chronic myeloid leukemia", "treatment", "diagnosis", "karyotype" and "cytogenetics". Specialized books and websites were also included. Detailed cytogenetic and molecular monitoring can assist in choosing the most effective drug for each patient, optimizing the treatment. Cytogenetics plays a key role in the detection of chromosomal abnormalities associated with malignancies, as well as the characterization of new alterations that allow more research and increase knowledge about the genetic aspects of these diseases. The development of new drugs, through the understanding of the molecular mechanisms involved, will allow a possible improvement in the survival of these patients.

OBJECTIVE: To identify chromosomal imbalances by whole-genome microarray-based comparative genomic hybridization (array-CGH) in DNA samples of neonates with congenital anomalies of unknown cause from a birth defects monitoring program at a public maternity hospital. METHODS: A blind genomic analysis was performed retrospectively in 35 stored DNA samples of neonates born between July of 2011 and December of 2012. All potential DNA copy number variations detected (CNVs) were matched with those reported in public genomic databases, and their clinical significance was evaluated. RESULTS: Out of a total of 35 samples tested, 13 genomic imbalances were detected in 12/35 cases (34.3%). In 4/35 cases (11.4%), chromosomal imbalances could be defined as pathogenic; in 5/35 (14.3%) cases, DNA CNVs of uncertain clinical significance were identified; and in 4/35 cases (11.4%), normal variants were detected. Among the four cases with results considered causally related to the clinical findings, two of the four (50%) showed causative alterations already associated with well-defined microdeletion syndromes. In two of the four samples (50%), the chromosomal imbalances found, although predicted as pathogenic, had not been previously associated with recognized clinical entities. CONCLUSIONS: Array-CGH analysis allowed for a higher rate of detection of chromosomal anomalies, and this determination is especially valuable in neonates with congenital anomalies of unknown etiology, or in cases in which karyotype results cannot be obtained. Moreover, although the interpretation of the results must be refined, this method is a robust and precise tool that can be used in the first-line investigation of congenital anomalies, and should be considered for prospective/retrospective analyses of DNA samples by birth defect monitoring programs.

ABSTRACT Fragile X syndrome is considered the main known cause of inherited learning disabilities and it is characterized by mutations in the FMR1 gene. Our aim was to report an unexpected detection of a patient with fragile X syndrome by GTG-Banding karyotype analysis (G-bands after trypsin and Giemsa). The karyotype analysis identified Xq27.3 fragility in 17% of the metaphases analyzed and in 54% when using TC 199, consistent with the cytogenetic diagnosis of the syndrome. This case was the sole one to present the fra(X) tests in the high-resolution karyotype analysis in our care service, contributing to future diagnoses of patients with history of developmental delay.

ABSTRACT We report the case of a patient with dystrophic epidermolysis bullosa (DEB) diagnosed by transmission electron microscopy (TEM), emphasizing the applications and importance of this technique in the health area. The patient was a male, the only child of young and non-consanguineous parents without similar cases in the family. The patient underwent a cutaneous biopsy in which TEM revealed sub-basal membrane involvement, confirming the diagnosis of DEB. Despite technological advances, TEM continues to play an important role in diagnosis and clinical research and is considered the best option for confirmation of diagnosis and subtypes of diseases such as epidermolysis bullosa (EB).

We report the first case of a child with 16p11.2 microduplication syndrome with increased fluid in the cisterna magna seen on magnetic resonance imaging (MRI). This finding may correspond to a Blake's Pouch Cyst (BPC) or a Mega Cisterna Magna (MCM), being impossible to differentiate through image examination. The molecular duplication was diagnosed using chromosomal microarray analysis with single nucleotide polymorphism (SNP). We review the clinical and neuroimaging features in published case reports in order to observe the findings described in the literature so far and present a skull three-dimensional model to contribute to a better understanding. Despite the variable expressivity of the syndrome being well known, there is no case described in the available literature that mentions the association of 16p11.2 microduplication and the presence of BPC or MCM seen in neuroimaging exams. This finding may represent an extension of the phenotype not yet reported or may present itself as a coincidence in a child with various malformations. [ABSTRACT FROM AUTHOR]

This section offers case reports in otorhinolaryngology including a study which found that congenital stenosis of the larynx is a rare differential diagnosis of the various cases of stridor in children, a hospital in Brazil reporting a rare case of a post-adenoidectomy granulation tissue obstruction that was solved by excision of the mass, and a hospital in Rio de Janeiro, Brazil reporting a rare case of Neurilemmoma.