RUIZ POZO, VIVIANA ALEJANDRA
Preferred name
RUIZ POZO, VIVIANA ALEJANDRA
Main Affiliation
CIGG - Centro de Investigación en Genética y Genómica
Web Site
ORCID
0000-0001-9301-2614
Scopus Author ID
57211950502
41 results
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Item type:Publication, Case Report: Genomic and clinical insights into MYBPC3-related hypertrophic cardiomyopathy in Ecuadorian patients: implications for sudden cardiac death risk(Frontiers Media SA, 2026-01-21); ; ; ; Hypertrophic cardiomyopathy (HCM) is the most common inherited cardiac disease and a leading cause of sudden cardiac death (SCD) in young adults and athletes. It exhibits marked clinical variability, which may be influenced by genetic background and environmental factors. Although MYBPC3 is the most frequently implicated gene, data from Latin American and admixed populations remain scarce. In this study, we describe three unrelated Ecuadorian patients with clinically diagnosed HCM who harbored MYBPC3 variants. Two patients carried likely pathogenic mutations (p.Glu258Lys and p.His875Profs*8), while novel missense variants (p.Ala536Pro and p.Thr274Met) were identified as variants of uncertain significance (VUS). Additional variants were detected in TTN, MYLK2, RYR1, SDHA, APOB, and JPH2, but given their classification as VUS or a lack of association with HCM, they are described only as incidental findings. An ancestry analysis revealed heterogeneous contributions of Native American, European, and African backgrounds, reflecting the admixed composition of the Ecuadorian population. This case series underscores the phenotypic heterogeneity of HCM, even among patients with MYBPC3 variants, and highlights the importance of genomic testing in underrepresented populations to improve diagnosis, family screening, and SCD risk stratification. 2026 Paz-Cruz, Guevara-Ramírez, Tamayo-Trujillo, Ruiz-Pozo, Cadena-Ullauri, Ibarra-Castillo, Laso-Bayas, Meza-Chico, Cabrera-Andrade and Zambrano. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Clinical, cytogenetic, and genomic analyses of an Ecuadorian subject with Klinefelter syndrome, recessive hemophilia A, and 1;19 chromosomal translocation: a case report(Springer Science and Business Media LLC, 2022-09-05); ; <jats:title>Abstract</jats:title><jats:sec> <jats:title>Background</jats:title> <jats:p>Hemophilia A is considered one of the most common severe hereditary disorders. It is an X-linked recessive disease caused by a deficiency or lack of function of the blood clotting factor VIII. Klinefelter syndrome is a genetic disorder that affects male individuals due to one or more extra X chromosomes, present in all cells or with mosaicism. The aneuploidy is due to either mitotic or meiotic chromosome non-disjunction. Chromosomal translocations are a group of genome abnormalities in which a region or regions of a chromosome break and are transferred to a nonhomologous chromosome or a new location in the same chromosome.</jats:p> </jats:sec><jats:sec> <jats:title>Case presentation</jats:title> <jats:p>Our subject was born in Ecuador at 36 weeks of gestation by vaginal delivery. At 3 months old, the Factor VIII activity measure showed a 23.7% activity indicating a diagnosis of mild hemophilia A. At 1 year old, the karyotype showed an extra X chromosome, consistent with a diagnosis of Klinefelter syndrome, and a translocation between the long arms of chromosomes 1 and 19, at positions q25 and q13, respectively.</jats:p> </jats:sec><jats:sec> <jats:title>Conclusions</jats:title> <jats:p>Klinefelter syndrome and hemophilia are a rare combination. In the present case report, the subject presents both, meaning that he has inherited one X chromosome from the father and one X chromosome from the mother. Since the father has severe hemophilia A; and the subject presents a below 40% Factor VIII activity, a skewed X inactivation is suggested. Additionally, the proband presents a translocation with the karyotype 47,XXY,t(1;19)(q25;q13). No similar report with phenotypic consequences of the translocation was found. The present report highlights the importance of a correct diagnosis, based not only on the clinical manifestations of a disease but also on its genetic aspects, identifying the value of integrated diagnostics. The subject presents three different genetic alterations, Klinefelter syndrome, hemophilia A, and a 1;19 chromosomal translocation.</jats:p> </jats:sec> - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Spectrum and Clinical Interpretation of TTN Variants in Ecuadorian Patients with Heart Disease: Insights into VUS and Likely Pathogenic VariantsThis study described TTN gene variants in Ecuadorian patients with hereditary cardiac diseases, integrating genetic ancestry to improve variant interpretation in an underrepresented population. Sixty patients with confirmed hereditary cardiac conditions were analyzed using the TruSight Cardio NGS panel (Illumina, San Diego, CA, USA), which targets 174 cardiac-associated genes. Bioinformatic analyses and classification were performed in accordance with ACMG/AMP guidelines, and ancestry inference was conducted using 46 Ancestry Informative Markers (AIM-InDels). From 4008 detected TTN variants, 29 variants of interest remained after filtering: 27 classified as variants of uncertain significance (VUS) and two as likely pathogenic. All variants were heterozygous and distributed across exons 3–358, primarily in the A-band region, commonly associated with cardiomyopathies and arrhythmic phenotypes. Two truncating variants (exons 267 and 272) met PVS1 criteria, while several missense variants (p.Ser91Gly, p.Pro12140Ser, p.Arg34653Cys) showed possible modulatory effects on hypertrophic or arrhythmic outcomes. Genetic ancestry revealed a predominant Native American background, followed by European and African components. These findings expand the understanding of TTN-related cardiac disease in Latin America, suggesting that TTN functions as a genetic modifier influencing disease expression. Incorporating ancestry information enhances genomic interpretation and supports precision medicine in diverse populations. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Identification of KIT and BRAF mutations in thyroid tissue using next-generation sequencing in an Ecuadorian patient: A case report(Frontiers Media SA, 2023-01-17); ; ; Cristhian Garcia<jats:sec><jats:title>Background</jats:title><jats:p>The incidence of thyroid cancer has increased worldwide. Ecuador presents the highest incidence among Latin American countries and the second around the world. Genetic alteration is the driving force for thyroid tumorigenesis and progression. The change from valine (V) to glutamic acid (E) at codon 600 of the BRAF gene (BRAF<jats:sup>Val600Glu</jats:sup>) is the most commonly reported mutation in thyroid cancer. Moreover, the BRAF mutation is not the only mutation that has been correlated with TC. For instance, mutations and overexpression of the KIT gene has been associated with different types of cancer, including lung and colon cancer, and neuroblastoma.</jats:p></jats:sec><jats:sec><jats:title>Case presentation</jats:title><jats:p>A woman in her early fifties, self-identified as mestizo, from Otavalo, Imbabura-Ecuador had no systemic diseases and denied allergies, but she had a family history of a benign thyroid nodule. Physical examination revealed a thyroid gland enlargement. The fine-needle aspiration biopsy indicated papillary thyroid cancer. The patient underwent a successful total thyroidectomy with an excellent recovery and no additional treatments after surgery. Using Next-Generation sequencing a heterozygous mutation in the BRAF gene, causing an amino acid change Val600Glu was identified. Similarly, in the KIT gene, a heterozygous mutation resulting in an amino acid change Leu678Phe was detected. Moreover, an ancestry analysis was performed, and the results showed 3.1% African, 20.9% European, and 76% Native American ancestry.</jats:p></jats:sec><jats:sec><jats:title>Conclusions</jats:title><jats:p>This report represents the genetic characteristics of papillary thyroid cancer in an Ecuadorian woman with a mainly Native American ethnic component. Further studies of pathological variants are needed to determine if the combined demographic and molecular profiles are useful to develop targeted treatments focused on the Ecuadorian population.</jats:p></jats:sec> - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Molecular mechanisms of semaglutide and liraglutide as a therapeutic option for obesity(Frontiers Media SA, 2024-04-29); ; ; Obesity, a chronic global health problem, is associated with an increase in various comorbidities, such as cardiovascular disease, type 2 diabetes mellitus, hypertension, and certain types of cancer. The increasing global prevalence of obesity requires research into new therapeutic strategies. Glucagon-like peptide-1 receptor agonists, specifically semaglutide and liraglutide, designed for type 2 diabetes mellitus treatment, have been explored as drugs for the treatment of obesity. This minireview describes the molecular mechanisms of semaglutide and liraglutide in different metabolic pathways, and its mechanism of action in processes such as appetite regulation, insulin secretion, glucose homeostasis, energy expenditure, and lipid metabolism. Finally, several clinical trial outcomes are described to show the safety and efficacy of these drugs in obesity management. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Population Admixture and APOB Variant Landscape in Ecuadorian Mestizo Patients with Cardiac Diseases: Potential Implications for Familial Hypercholesterolemia GeneticsApolipoprotein B (APOB) is a key structural component of atherogenic lipoproteins and one of the principal genes implicated in familial hypercholesterolemia (FH). However, APOB genetic variation remains poorly characterized in Latin American and admixed populations. In this study, we performed a descriptive analysis of APOB variants in 60 Ecuadorian mestizo patients with inherited cardiac conditions using next-generation sequencing (NGS) and genetic ancestry inference. A total of 227 APOB variants were identified, the majority of which were classified as benign (n = 220) or likely benign (n = 3) according to ACMG criteria, while three variants were classified as variants of uncertain significance (VUS). The most frequently observed variants included rs1042034, rs679899, rs676210, and rs1367117. Comparative allele-frequency analyses using ALFA and PAGE Latin American reference datasets demonstrated that the APOB variant frequencies observed in the cohort were comparable to those reported in other Latin American populations, reflecting the admixed genetic background of Ecuadorian mestizos, predominantly of Native American and European ancestry. No pathogenic APOB variants were detected. Although lipid measurements were not available and genotype–phenotype associations could not be assessed, this study provides the first comprehensive overview of APOB variation in Ecuadorian mestizo individuals. These findings expand population-specific genomic data for an underrepresented group and underscore the importance of regional reference datasets for accurate variant interpretation in admixed populations. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Case Report Series: Genetic and clinical characterization of long QT syndrome in admixed Ecuadorian patients and its implications for sudden cardiac death risk(Frontiers Media SA, 2026-02-12); ; ; ; Long QT syndrome (LQTS) is a hereditary cardiac channelopathy associated with delayed ventricular repolarization and increased risk of life-threatening arrhythmias and sudden cardiac death. We report three Ecuadorian patients with LQTS, each presenting distinct clinical features and carrying pathogenic or likely pathogenic variants in KCNH2 or KCNQ1. Subject A, an 18-year-old woman with exertion-related syncope and a QTc of 520 ms, was diagnosed with LQT2 due to a KCNH2 p.Ala614Val variant. Subject B, a 3-year-old girl with congenital deafness and a QTc of 580 ms, was diagnosed with Jervell and Lange-Nielsen syndrome (JLNS), harboring a homozygous KCNQ1 p.Arg192Cys variant. Subject C, a 44-year-old man with recurrent syncope misdiagnosed as epilepsy and a strong family history of sudden death, was found to carry a KCNH2 p.Val612Met variant and had a QTc of 600 ms. All variants were classified according to ACMG/AMP guidelines and supported by in silico and functional data. Ancestry analysis provided additional genomic context in this admixed population. These cases underscore the clinical utility of integrating ECG findings, genetic testing, and ancestry-informed interpretation to improve diagnostic accuracy and personalize management in patients with inherited arrhythmia syndromes. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Evaluating Liquid Biopsy for Circulating Tumor DNA (ctDNA) Detection as a Complementary Diagnostic Tool in Thyroid Cancer Among Ecuadorian WomenThyroid cancer (TC) is the most common endocrine malignancy, with a rising global incidence. In Ecuador, TC rates are among the highest worldwide. Generally, fine-needle aspiration (FNA) remains the standard diagnostic tool; however, due to its limitations, alternative or complementary approaches are required. In this context, liquid biopsy, particularly circulating tumor DNA (ctDNA), offers a promising, minimally invasive option for tumor genotyping. Objective: This study evaluated the concordance between genetic variants identified in ctDNA and tumor tissue. Thirty-six women with papillary thyroid cancer were included. Tumor tissue and blood samples were collected, and DNA was extracted. Next-Generation Sequencing (NGS) using the TruSight Tumor 15 panel identified genetic variants in both ctDNA and tumor DNA. Variant pathogenicity was assessed following ACMG guidelines. Genetic ancestry was determined using Ancestry Informative Markers (AIMs). A total of 71 cancer-associated variants were detected, with 81.69% concordance between tumor DNA and ctDNA. TP53 was the most frequently mutated gene. While most pathogenic variants were found in tumor tissue, some variants appeared exclusively in ctDNA samples on specific patients, suggesting tumor heterogeneity. Ancestry analysis revealed a predominant Native American component (62.4%). Liquid biopsy demonstrates high concordance with tumor tissue analysis and holds potential as a complementary diagnostic tool for thyroid cancer. However, challenges such as low ctDNA yield and underrepresentation in genetic databases highlight the need for improved protocols and increased inclusion of admixed populations in genomic studies. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Effect of diet on the microbiota and immune system in patients with systemic lupus erythematosus(Informa UK Limited, 2024-11-30); ; ; ; Systemic lupus erythematosus (SLE) is a chronic autoimmune disease characterized by widespread inflammation and organ damage. Studies indicate that diet significantly influences the gut microbiota, which, in turn, affects the immune system. This article explores gut microbiota dysbiosis in SLE patients and potential mechanisms related to dietary interventions and immune function. It highlights specific dietary patterns, such as a high-fibre diet and the Mediterranean diet, that may modulate the diversity and activity of the gut microbiota. The interaction between altered microbiota and immune responses, including the regulation of inflammatory cytokines, intestinal barrier permeability, and autoantibody production is examined. This review highlights the importance of personalized dietary strategies to modulate the diversity and activity of the gut microbiota by enhancing the immune response and potentially mitigating disease progression. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Identification of a novel NKX2-5 variant in a young Ecuadorian patient with atrioventricular block and bradycardia: a case report(Frontiers Media SA, 2025-04-03); ; ;