Down syndrome: A case report of a patient with a rare genetic abnormality
Main Article Content
Abstract
Down syndrome (DS) is one of the most common genetic syndromes. The phenotypic manifestations in affected individuals are severe, involving multiple organ systems, causing intellectual disability and multiple congenital abnormalities. The most frequent congenital defects include ventricular septal defects, atriventricular septal defect, Hirschsprung disease, duodenal atresia or stenosis, and an increased risk of acute leukemia and Alzheimer's disease. This study reports a case of a patient with Down syndrome who has a rare genetic abnormality that has not been previously described in the literature. Furthermore, the study updates the current understanding of Down syndrome, the genetic testing techniques used in diagnosis, and the application of International System for Human Cytogenomic Nomenclature (ISCN) to describe the genetic abnormality. Conclusion: Using cytogenetic tests, including chromosome analysis and Fluorescence in situ Hybridization (FISH), the patient was diagnosed with translocation Down syndrome accompanied by an additional maternal chromosomal translocation:46,XY,der(7)t(7;14)(p13;q24)dmat,der(14;21)(q10;q10)dn t(7;14)dmat,+21.
Article Details
Keywords
Translocation Down syndrome, balanced chromosomal translocation International System for Human Cytogenomic Nomenclature
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