Mechanisms of Chromosomal Aneuploidy

Understanding the mechanisms of chromosomal aneuploidy is fundamental for Zambian tertiary students in genetics, reproductive biology, and embryology. This topic explores the cellular errors that lead to an abnormal number of chromosomes, with a primary focus on nondisjunction during meiosis I and II and mitotic anaphase lag. Students will examine how these errors result in gametes with missing or extra chromosomes, leading to conditions like trisomy 21 (Down syndrome), Turner syndrome (45,X), and Klinefelter syndrome (47,XXY). The influence of advanced maternal age on meiotic nondisjunction is also covered. This knowledge aligns with advanced diploma and degree curricula in biomedical sciences across Zambia, equipping learners for examinations and for roles in prenatal diagnostics, genetic counselling, and assisted reproductive technologies. A clear grasp of these mechanisms is essential for addressing infertility, miscarriage, and congenital disorders in clinical practice.