The exact incidence of<unk>  is unknown. It is one of the more common conditions in a group known as mitochondrial diseases. Together, mitochondrial diseases occur in about 1 in 4,000 people.
MELAS syndrome
Bannayan–Riley–Ruvalcaba syndrome
Pashayan syndrome
Fitzsimmons–Guilbert syndrome
Teunissen–Cremers syndrome
Fryns-Aftimos syndrome
Abruzzo–Erickson syndrome
Berk–Tabatznik syndrome