What genetic anomaly is present in Down Syndrome?

What genetic anomaly is present in Down Syndrome?

• A. Monosomy 21
• B. Trisomy 21
• C. Deletion of chromosome 21
• D. Translocation of chromosome 18

Answer: (B)

Down Syndrome, also known as Trisomy 21, is characterized by the presence of an extra copy of chromosome 21. This genetic anomaly occurs due to nondisjunction during cell division, which results in the individual having three copies of this chromosome instead of the usual two. The additional genetic material from this extra chromosome affects physical growth, intellectual development, and various health issues often associated with Down Syndrome. This condition is referred to as "trisomy" because the prefix "tri-" denotes three, indicating that chromosome 21 is present in triplicate in the affected individual. Understanding the underlying genetic cause is crucial, as it helps inform the clinical features and potential interventions for those with Down Syndrome.

Down Syndrome, also known as Trisomy 21, is characterized by the presence of an extra copy of chromosome 21. This genetic anomaly occurs due to nondisjunction during cell division, which results in the individual having three copies of this chromosome instead of the usual two. The additional genetic material from this extra chromosome affects physical growth, intellectual development, and various health issues often associated with Down Syndrome.

This condition is referred to as "trisomy" because the prefix "tri-" denotes three, indicating that chromosome 21 is present in triplicate in the affected individual. Understanding the underlying genetic cause is crucial, as it helps inform the clinical features and potential interventions for those with Down Syndrome.