World Down Syndrome Day is celebrated every year on March 21 to spread awareness about the discrimination faced by individuals with Down syndrome across the world. The main aim of this international day is to raise awareness about Down syndrome and help those individuals who are suffering from this condition.

Down syndrome is a genetic condition or disorder which causes slight to significant development and physical problems. Individuals with Down Syndrome are born with extra chromosomes that affect both physically and mentally. Down syndrome is caused when abnormal cell division involving chromosome 21 occurs and these cell division abnormalities that may result in an extra partial or full chromosome 21. A medical word to have an extra copy of a chromosome is trisomy thus Down syndrome is also called as Trisomy 21. This extra copy changes the body and brain development of babies which may cause physical and mental challenges or issues for a baby. It also varies in severity among people which causes developmental delays and lifelong disability. Down syndrome is one of the most common genetic chromosomal conditions or disorders that may also cause learning disabilities in children. It also commonly causes several other medical abnormalities including gastrointestinal disorders.

Down Syndrome is also a neurodevelopmental disorder, which may affect the physical and mental conditions of an individual. Several symptoms of Down syndrome are intellectual disability, development delays, small hands and feet, loose joints, distinct facial appearance, and many more. There is no specific treatment for Down syndrome but several physical and developmental therapies to help individuals with Down syndrome are behavioral counselling, physical, and speech therapy, occupational therapy, and many more. 

The United Nations chose the date of March 21 to observe World Down Syndrome Day across the world. Down syndrome is caused by triplication (trisomy) of the 21^st chromosome. This international day also highlights the full support of close relatives and friends together to help those individuals who are suffering from Down syndrome.