400
Down syndrome is an example of a _______ cause of intellectual disability.
What is Genetic?
Prenatal
Genetic conditions. Sometimes disability is caused by abnormal genes inherited from parents, errors when genes combine, or other reasons. The most prevalent genetic conditions include Down syndrome, Klinefelter's syndrome, Fragile X syndrome (common among boys), Neurofibromatosis, congenital hypothyroidism, Williams syndrome, Phenylketonuria (PKU), and Prader-Willi syndrome.
Inborn Errors metabolism, brain malformation, maternal disease when the fetus does not develop properly
environmental - alcohol, toxins, other drugs, and teratogens
Perinatal
Labor & delivery events leading to encephalopathy
Postnatal
Hypoxy, TBI, infection, demylenation disorders, seizures, severe chronic social deprivation, & toxin exposure