Types of Down Syndrome Disorders Diagnosed at the First International Laboratory from 2020 to 2025
DOI:
https://doi.org/10.54361/LJMR.20.2.40Keywords:
Down syndrome, Trisomy 21, maternal age, consanguinity, Benghazi, karyotypingAbstract
Background: Down syndrome is the most common chromosomal disorder worldwide, associated with distinct cytogenetic patterns and maternal risk factors. Understanding these features in Benghazi is essential for guiding local healthcare interventions. Aim: To determine the prevalent cytogenetic types and demographic factors associated with Down syndrome diagnosed at Benghazi’s First International Laboratory. Materials and Methods This retrospective study analyzed 200 karyotype records from 2020 to 2025. Cytogenetic classification and demographic data, including maternal age and consanguinity, were assessed. Results: Trisomy 21 accounted for the majority of cases (82%), followed by mosaicism (12%) and translocation (6%). Advanced maternal age (>35 years) was significantly associated with Trisomy 21, while consanguinity was observed in 30% of translocation cases. Conclusions: Trisomy 21 is the predominant form of Down syndrome in Eastern Libya and is strongly linked to advanced maternal age. Consanguinity may contribute to rarer subtypes such as translocation. These findings highlight the importance of maternal health awareness and genetic counseling initiatives in the region.
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Copyright (c) 2026 Abeer Hussein Amer, Fatma H. Boshahma, Tarik Shoeib, Rayan Khaled, Kindah Salem, Mardiah Mustafa, Fatma Issa (Author)
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