Down’s Syndrome

Down syndrome (DS) or Down’s syndrome is also known as trisomy 21. It is a genetic disorder caused by the presence of extra chromosome 21 .It is typically associated with a delay in cognitive ability (mental retardation or MR) and physical growth and a particular set of facial characteristics.
The average IQ of young adults with Down syndrome is around 50 whereas young adults without the condition typically have an IQ of 100.