What is Down syndrome?
Down syndrome is a genetic disorder caused by the presence of an extra copy of chromosome 21 (or a part of it), instead of the usual two, which is why it is also called trisomy 21. It is characterized by the presence of a variable degree of cognitive disability and peculiar physical features that give it a recognizable appearance. It is the most common cause of congenital mental cognitive disability and owes its name to John Langdon Haydon Down who was the first to describe this genetic alteration in 1866, although he never discovered the causes that produced it. In July 1958, a young researcher named Jérôme Lejeune discovered that the syndrome is an alteration in the aforementioned pair of chromosomes.World Down Syndrome Day (WDSD) is marked each year on March 21, beginning in 2006. The 21st day of March (the 3rd month of the year) was selected to signify the uniqueness of the triplication (trisomy) of the 21st chromosome which causes Down syndrome.
Every year on March 21, World Down Syndrome Day is observed to create awareness about Down syndrome. It is a condition in which a child is born with an extra 21st chromosome.
Every year on March 21, World Down Syndrome Day is observed to create awareness about Down syndrome. It is a condition in which a child is born with an extra 21st chromosome.
