Multi‐institutional experience of genetic diagnosis in Ecuador: National registry of chromosome alterations and polymorphisms
Journal
Molecular Genetics & Genomic Medicine
ISSN
2324-9269
Date Issued
2019-12-12
Author(s)
Verónica Yumiceba
Germania Moreta
Rosario Paredes
Mónica Ruiz
Ligia Ocampo
Arianne Llamos Paneque
Catalina Ochoa Pérez
Juan Carlos Ruiz‐Cabezas
Jenny Álvarez Vidal
Idarmis Jiménez Torres
Ramón Vargas‐Vera
Fernando Cruz
Víctor Hugo Guapi N
Martha Montalván
Sara Meneses Álvarez
Maribel Garzón Castro
Elizabeth Lamar Segura
María Augusta Recalde Báez
María Elena Naranjo
Nina Tambaco Jijón
María Sinche
Pedro Licuy
Ramiro Burgos
Fabián Porras‐Borja
Gabriela Echeverría‐Garcés
Andy Pérez‐Villa
Isaac Armendáriz‐Castillo
Jennyfer M. García‐Cárdenas
Santiago Guerrero
Patricia Guevara‐Ramírez
Andrés López-Cortés
Paola E. Leone
Abstract
<jats:title>Abstract</jats:title><jats:sec><jats:title>Background</jats:title><jats:p>Detection of chromosomal abnormalities is crucial in various medical areas; to diagnose birth defects, genetic disorders, and infertility, among other complex phenotypes, in individuals across a wide range of ages. Hence, the present study wants to contribute to the knowledge of type and frequency of chromosomal alterations and polymorphisms in Ecuador.</jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p>Cytogenetic registers from different Ecuadorian provinces have been merged and analyzed to construct an open‐access national registry of chromosome alterations and polymorphisms.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>Of 28,806 karyotypes analyzed, 6,008 (20.9%) exhibited alterations. Down syndrome was the most frequent autosome alteration (88.28%), followed by Turner syndrome (60.50%), a gonosome aneuploidy. A recurrent high percentage of Down syndrome mosaicism (7.45%) reported here, as well as by previous Ecuadorian preliminary registries, could be associated with geographic location and admixed ancestral composition. Translocations (2.46%) and polymorphisms (7.84%) were not as numerous as autosomopathies (64.33%) and gonosomopathies (25.37%). Complementary to conventional cytogenetics tests, molecular tools have allowed identification of submicroscopic alterations regions or candidate genes which can be possibly implicated in patients' symptoms and phenotypes.</jats:p></jats:sec><jats:sec><jats:title>Conclusion</jats:title><jats:p>The Ecuadorian National Registry of Chromosome Alterations and Polymorphisms provides a baseline to better understand chromosomal abnormalities in Ecuador and therefore their clinical management and awareness. This data will guide public policy makers to promote and financially support cytogenetic and genetic testing.</jats:p></jats:sec>