National Seroprevalence of in Chile, 2016-2017.

is an intracellular bacterium and the cause of the zoonotic infection, Q fever. National surveillance data on seroprevalence is currently not available for any South American country, making efforts of public health to implement strategies to mitigate infections in different at-risk groups within the population extremely challenging. In the current study, we used two commercial anti- immunoassays to screen sera collected from a sample of the Chilean population as part of a 2016-2017 national health survey ( = 5166), nationwide and age-standardized.

Evidence of Q Fever and Rickettsial Disease in Chile.

Q fever and rickettsial diseases occur throughout the world and appear to be emergent zoonoses in Chile. The diagnosis of these diseases is currently uncommon in Chile, as their clinical presentations are non-specific and appropriate diagnostic laboratory assays are of limited availability. During a recent outbreak of undiagnosed human atypical pneumonia, we serologically investigated a series of 357 cases from three regions of southern Chile.

and founder mutations account for 78% of germline carriers among hereditary breast cancer families in Chile.

Identifying founder mutations in and in specific populations constitute a valuable opportunity for genetic screening. Several studies from different populations have reported recurrent and/or founder mutations representing a relevant proportion of mutation carriers. In Latin America, only few founder mutations have been described.

Germline Mutations in PALB2, BRCA1, and RAD51C, Which Regulate DNA Recombination Repair, in Patients With Gastric Cancer.

Up to 10% of cases of gastric cancer are familial, but so far, only mutations in CDH1 have been associated with gastric cancer risk. To identify genetic variants that affect risk for gastric cancer, we collected blood samples from 28 patients with hereditary diffuse gastric cancer (HDGC) not associated with mutations in CDH1 and performed whole-exome sequence analysis. We then analyzed sequences of candidate genes in 333 independent HDGC and non-HDGC cases.

Different Array CGH profiles within hereditary breast cancer tumors associated to BRCA1 expression and overall survival.

Background: Array CGH analysis of breast tumors has contributed to the identification of different genomic profiles in these tumors. Loss of DNA repair by BRCA1 functional deficiency in breast cancer has been proposed as a relevant contribution to breast cancer progression for tumors with no germline mutation. Identifying the genomic alterations taking place in BRCA1 not expressing tumors will lead us to a better understanding of the cellular functions affected in this heterogeneous disease.

miR-146a and miR-638 in BRCA1-deficient triple negative breast cancer tumors, as potential biomarkers for improved overall survival.

Background: Mechanisms that lead to the reduced expression of BRCA1 in triple-negative breast cancer (TNBC) tumors are not fully understood. A possible cause is overexpression of miR-146a and miR-638, which regulate BRCA1 expression in other cancers.

Objective: To evaluate the expression of these microRNAs in relation to BRCA1 expression in TNBC tumors.

BRCA1 and BARD1 colocalize mainly in the cytoplasm of breast cancer tumors, and their isoforms show differential expression.

BRCA1 has been found to be absent or miss localized in the cytoplasm in a relevant proportion of breast cancer tumors with no germline mutations. BRCA1 main function is in the nucleus, and its interaction with BARD1 is relevant for its nuclear translocation and retention. Our aim was to analyze the sub-cellular localization of BRCA1 and BARD1 in breast cancer tumors, and determine the level of expression of their splice variants BRCA1-Δ11q and BARD1-α and BARD1-β.

Silencing of tumor suppressor genes RASSF1A, SLIT2, and WIF1 by promoter hypermethylation in hereditary breast cancer.

Promoter hypermethylation is gaining strength as one of the main mechanisms through which tumor suppressor genes are silenced during tumor progression. Three tumor suppressor genes are frequently found methylated in their promoter, in concordance with absence of expression, RASSF1A, SLIT2, and WIF1. In addition, a previous array-CGH analysis from our group showed that these genes are found in deleted genomic regions observed in hereditary breast cancer tumors.

Promoter hypermethylation of BRCA1 correlates with absence of expression in hereditary breast cancer tumors.

Germline mutations in BRCA1 account for a low proportion of hereditary cases in diverse populations. Several efforts have been made to find new genes involved in the inheritance of breast cancer with no success until today. The participation of BRCA1 in the development of breast cancer has been proposed in several studies where hypermethylation of its promoter and a decrease in expression has been reported for sporadic cases and one study on familial cases.

ATM allelic variants associated to hereditary breast cancer in 94 Chilean women: susceptibility or ethnic influences?

Besides BRCA1 and BRCA2, two genes accounting for a small proportion of breast cancer cases, ATM has been widely proposed as a low-penetrance susceptibility gene. Several nucleotide changes have been proposed to be associated with breast cancer, still remaining a high controversy in this sense. We screened the ATM gene in 94 breast cancer patients selected from 78 high-risk families, not presenting a mutation in BRCA1 or BRCA2.

Incidence of BRCA1 and BRCA2 mutations in 54 Chilean families with breast/ovarian cancer, genotype-phenotype correlations.

Our aim was to analyze the incidence of mutations in BRCA1 and BRCA2 genes in 54 families with breast/ovarian cancer. Families were selected from three Institutions following the standard criteria for hereditary breast/ovarian cancer. PCR amplification of all exons was performed, followed by SSCP, heteroduplex, PTT and sequencing analysis.