patau syndrome

Puberty (13), Election age (18), and Drinking age (21)

Puberty for Patau syndrome, caused by trisomy 13

Election for Edwards syndome, caused by trisomy 18

Drinking for Down syndrome, caused by trisomy 21

AND this list is in reverse order of frequency of trisomies resulting in live births (Down most common, then Edward, then Patau).

I always find this super difficult, but it turns out First Aid has a mnemonic for this.

Patau syndrome/Trisomy 13

Trisomy 13 occurs when extra DNA from chromosome 13 appears in some or all of the body’s cells. This abnormal chromosome count interferes with development of certain organs such as the heart and kidneys. Similar to all nondisjunction defects (Down syndrome, Edwards syndrome), there is an increased likelihood for this syndrome when the mother is older, 31 years old average.


  • Cleft lip/palate
  • Close set eyes (severe cases include Cyclopia)
  • Extra fingers/toes (polydactyly)
  • Hernias
  • Clenched hands
  • Low set ears
  • Skeletal abnormalities
  • Seizures
  • Coloboma (cleft in the iris)
  • Mental retardation