Down syndrome is a genetic disorder caused when abnormal cell division results in an extra full or partial copy of chromosome 21. This extra genetic material causes the developmental changes and physical features of Down syndrome.

Children with down syndrome usually have a charachteristic facial feature that includes:

• Flattened face
• Small head
• Short neck
• Protruding tongue
• Upward slanting eyelids (palpebral fissures)
• Unusually shaped or small ears
• Poor muscle tone
• Broad, short hands with a single crease in the palm
• Relatively short fingers and small hands and feet
• Excessive flexibility
• Tiny white spots on the colored part (iris) of the eye called Brushfield’s spots
• Short height
• Infants with Down syndrome may be average size, but typically they grow slowly and remain shorter than other children the same age.

Other symptoms include:

• Delayed development
• Speech delay
• Congenital heart disease.
• Thyroid disorder.
• Obsturctive sleep apnea.
• Flaccid muscles.
• Recurrent coryza.
• Lowered immune functioning.
• Thickening of skin of palms and soles.
• Mouth breathing.