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A ~3-kb deletion-type DNA copy number variation (CNV, esv3587290) located at intron 7 of the VANGL1 gene (1p13.1, MIM*610132) has been proposed as a genetic factor in lupus nephritis (LN) development in adult systemic lupus erythematosus (SLE) patients across European-descent populations, but its replication in other ethnicities has been inconsistent and its association with LN in childhood-onset SLE (cSLE) remains unknown. Here, we performed an exploratory association study in a sample of 66 unrelated cSLE Mexican patients (11 males, 55 females; ages 7.8 to 18.6 years). Two stratified groups were compared: cSLE patients with (N = 39) or without (N = 27) LN, as diagnosed by renal biopsy (N = 17), proteinuria (N = 33), urinary protein-creatinine ratio > 0.2 (N = 34), and erythrocyturia and/or granular casts in urinary sediment (N = 16). For esv3587290 CNV genotyping, we performed an end-point PCR assay with breakpoint confirmation using Sanger sequencing. We also determined the allelic frequencies of the esv3587290 CNV in 181 deidentified ethnically matched individuals (reference group). The obtained genotypes were tested for Hardy-Weinberg equilibrium using the χ2 test. Associations between LN and esv3587290 CNV were tested by calculating the odds ratio (OR) and using Pearson's χ2 tests, with a 95% confidence interval and p ≤ 0.05. The esv3587290 CNV allele (OR 0.108, 95% CI 0.034-0.33, p = 0.0003) and the heterozygous genotype (OR 0.04, 95% CI 0.119-0.9811, p = 0.002) showed a significant protective effect against LN development. Finally, we characterized the precise breakpoint of the esv3587290 CNV to be NG_016548.1(NM_138959.3):c.1314+1339_1315-897del in our population. This report supports the notion that a broad genetic heterogeneity underlies the susceptibility for developing LN.

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Introduction: Congenital heart disease (CHD) is the most common type of congenital defect reported to be one of the leading causes of mortality in the first year of life. Microdeletion and microduplication syndromes (MMS) are associated with cardiac malformations. Understanding which genetic factors are involved in these conditions directly impacts treatment decisions. We aimed to identify the occurrence of genetic alterations and their association with MMS in CHD pediatric patients evaluated in a reference service of Southern Brazil. Methods: Participants were recruited during 2010 in the intensive care unit of a pediatric hospital. MMs and regions of chromosome 22 were screened by SALSA MLPA Probemix P245 Microdeletion Syndromes-1A kit for detection of copy number variations (CNVs). Results: MMS were detected in 11 from 207 patients (5.3%). Heterozygous deletion in the 22q11.2 chromosome region was the most prevalent CNV (5 from 11 patients). Also, atypical RTDR1 deletion and 22q11.2 duplication were detected. MLPA was able to reveal microdeletions in SNRPN and NF1 genes in patients with a normal karyotype and FISH. Conclusion: Our study reports the prevalence and variability of genomic alterations associated with MMS in CHD pediatric patients. The results by MLPA are of great help in planning and specialized care.

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Introduction: Congenital abnormalities could be caused by copy number variation or homozygous variants inherited of parental consanguineous. Purpose. Objetive: To show copy number variants and regions of homozygosity in neonates with malformative syndrome or one congenital anomaly major associated to facial dysmorphia or hypotonia. Methodology: Performed chromosomal microarray analysis (CGH/SNP) to 60 neonates with congenital anomalies born in Hospital Antonio Lorena and Hospital Regional Cusco. Results: 70% of the newborns had an abnormal test (n=42); 48,3% (n=29) patients had with regions of homozygosity above to 0,5% (endogamy coefficient up to 1/64). Pathogenic or likely pathogenic copy number variations with or without region of homozygosity were present in 14,2% (n=6) newborns with congenital abnormalities. We founded five patients with uncertain pathogenic copy number variations that have not been described previously and might correlate with phenotype. Conclusion: We founded a similar frequency of CNV in newborns with congenital abnormalities compared to previous reports. Nonetheless, parental consanguinity was increased compared to other countries of South America. This is the first report in Peru that showed to CMA as a useful diagnostic method in patients with congenital abnormalities and is pioneer in relation to other countries in Latinoamerica.

Introducción: Las variantes en el número de copias son un tipo de cambios en el genoma provocan anomalías congénitas. Objetivo: Determinar las variantes en el número de copias y el grado de consanguinidad parental en neonatos con síndromes malformativos o una anomalía congénita mayor asociado a dismorfia facial o hipotonía. Materiales y métodos: Se realizó el análisis cromosómico por micromatrices a 60 neonatos con anomalías congénitas evaluados en los Hospitales Antonio Lorena y Regional de Cusco. Resultados: Del total de pacientes estudiados, el 70% tuvo un resultado anómalo; de los cuales en el 14,2% de los recién nacidos se encontraron variantes en el número de copias patogénicas o probablemente patogénicas asociadas o no a regiones de homocigosidad que tuvieron relación con las anomalías congénitas descritas. En el 48,3% de los recién se encontró regiones de homocigosidad mayores a 0,5% (coeficiente de endogamia superior a 1/64). Por otro lado, encontramos cinco variantes en el número de copias de patogenicidad desconocida que no se han descrito anteriormente y podrían estar relacionadas con el fenotipo. Conclusión: Nuestra tasa de detección de las variantes en el número de copias está en relación con los reportes internacionales previos. Sin embargo, el porcentaje de neonatos con consanguinidad parental se encuentra por encima de lo reportado previamente, siendo superior a otras regiones de Sudamerica. Este es el primer reporte en el Perú, y es pionero en Latinoamérica al utilizar el análisis cromosómico por micromatrices en esta cohorte específica de pacientes.

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BACKGROUND: Copy Number variation (CNVs) in genes related to drug absorption, distribution, metabolism and excretion (ADME) are relevant in the interindividual variability of drug response. Studies of the CNVs in ADME genes in Latin America population are lacking. The objective of the study was to identify the genetic variability of CNVs in CYP-450 and GST genes in a subgroup of individuals of Colombian origin. METHODS: Genomic DNA was isolated from 123 healthy individuals from a Colombian population. Multiplex Ligation-Dependent Probe Amplification (MLPA) was performed for the identification of CNVs in 40 genomic regions of 11 CYP-450 and 3 GST genes. The genetic variability, allelic and genotypic frequencies were analyzed. RESULTS: We found that 13 out of 14 genes had CNVs: 5 (35.7%) exhibited deletions and duplications, while 8 (57.1%) presented either deletions or duplications.. 33.3% of individuals carried deletions and duplications while 49.6% had a unique type of CNV (deletion or duplication). The allelic frequencies of the CYP and GST genes were 0 to 47.6% (allele null), 0 to 17.5% (duplicated alleles) and 37 to 100% (normal alleles). CONCLUSIONS: Our results describe, for the first time, the genomic profile of CNVs in a subgroup of Colombian population in GST and CYP-450 genes. GST genes indicated greater genetic variability than CYP-450 genes. The data obtained contributes to the knowledge of genetic profiles in Latin American subgroups. Although the clinical relevance of CNVs has not been fully established, it is a valuable source of pharmacogenetic variability data with potential involvement in the response to medications.

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Type 2 diabetes (T2D) is a disease characterized by a deficiency in production or action of insulin. It is the result mainly of the interaction of the environment, lifestyle, as well as genetic factors. It is considered as one of the major health issues in the world because it affects severely the psychological well-being and overall life quality. Recently it has been shown that DNA copy number variations (CNVs) are associated with several diseases, including obesity and T2D. The CNVs are present from 9 to 18 % of the genome and can modify the expression levels of mRNA and proteins encoded by genes located near their localization. Less is known about their contribution to the pathogenesis of metabolic diseases, which is necessary to characterize so that these variations can be potentially used as biomarkers of genetic risk CNVs of T2D.

La diabetes tipo 2 (DT2) es una enfermedad caracterizada por una deficiencia en la producción o acción de la insulina; es el resultado de la interacción principalmente de factores ambientales, el estilo de vida, asícomo factores genéticos. Se considera como uno de los problemas de salud más importantes en el mundo debido a que afecta seriamente la independencia, el bienestar psicológico y en general la calidad de vida. Recientemente se ha demostrado que las variaciones en el número de copias de ADN (CNV, del inglés copy number variations) se asocian con diferentes enfermedades, entre ellas la obesidad y DT2. Las CNV se presentan en el 9 al 18 % del genoma y pueden modificar los niveles de expresión de mRNA y proteína codificados por genes cercanos a su ubicación. Poco se conoce acerca de su contribución en la patogénesis de las enfermedades metabólicas, por lo cual es necesario caracterizar estas variaciones para que potencialmente sean utilizadas como biomarcadores genéticos de riesgo de DT2.

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