{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,7]],"date-time":"2026-10-07T16:06:44Z","timestamp":1791389204019,"version":"4.3.3"},"reference-count":37,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2025,4,4]],"date-time":"2025-04-04T00:00:00Z","timestamp":1743724800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Cardiovasc. Med."],"abstract":"<jats:p>Cardiovascular diseases (CVDs) are the leading global cause of mortality, with South America reflecting similar trends. Among congenital heart diseases (CHDs), atrioventricular (AV) block is included. AV block is a condition defined by abnormal electrical signal transmission between the atria and ventricles. Advances in Next-Generation Sequencing (NGS) have facilitated the identification of genetic variants associated with cardiac disorders, such as AV block. Notably, the transcription factor NKX2-5 plays a crucial role in heart development and function, and mutations in this gene have been linked to bradycardia and AV block. This article describes the case report of a young Ecuadorian child diagnosed with AV block and bradycardia. Furthermore, by performing NGS, a missense variant, p.(Tyr274Ser) substitution, in the <jats:italic>NKX2-5<\/jats:italic> gene has been identified and classified as a variant of uncertain significance (VUS). Ancestral analysis has shown a genetic background of 16.5% African, 45.9% European, and 37.6% Native American. These findings suggest a potential association between the identified <jats:italic>NKX2-5<\/jats:italic> variant and the patient's phenotype, highlighting the importance of integrating genomic and ancestral analyses to advance personalized diagnostics and therapeutics in diverse populations, such as the mestizo population.<\/jats:p>","DOI":"10.3389\/fcvm.2025.1552423","type":"journal-article","created":{"date-parts":[[2025,4,4]],"date-time":"2025-04-04T12:10:54Z","timestamp":1743768654000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":2,"title":["Identification of a novel NKX2-5 variant in a young Ecuadorian patient with atrioventricular block and bradycardia: a case report"],"prefix":"10.3389","volume":"12","author":[{"given":"Viviana 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