An extra copy of chromosome 21 causes Down Syndrome. This can happen due to abnormal cell division during the development of the sperm or egg.

Prenatal screening tests can indicate Down syndrome. Diagnostic tests like chorionic villus sampling and amniocentesis are used to confirm a diagnosis.

There are three types: trisomy 21, Mosaic Down Syndrome, and Translocation Down Syndrome, each varying in the presence of the extra chromosome 21.

Most cases of Down Syndrome are not inherited. However, Translocation Down Syndrome can be passed from parent to child.

Complications may include congenital heart defects, gastrointestinal issues, and an increased risk for conditions like leukemia and dementia.

With advancements in medical care, the life expectancy for individuals with Down Syndrome has increased significantly, with many living into their 60s and beyond.

Down Syndrome cannot be prevented. However, genetic counseling before pregnancy can provide valuable information for high-risk individuals.