<unk>  is an extremely rare condition, prevalent among less than one in a million of individuals. As of 2021, only four cases have been characterized in literature.
Abruzzo–Erickson syndrome
XMEN disease
Fanconi–Bickel syndrome
Smith–Fineman–Myers syndrome
Schwartz–Matsuo syndrome
Sanjad-Sakati syndrome
MELAS syndrome
Fitzsimmons–Guilbert syndrome