Andrew 165 Class Picture | Andrew CD Discovers Classrooms 165 & 202 celebrated World Down Syndrome Day on March 21st. Down syndrome (or Trisomy 21) is a condition in which a person has an extra chromosome. Chromosomes are “packages” of genes in the body. They determine how a baby’s body forms and functions as it grows. Around 1 in every 800 babies will be born with Down syndrome. |