Causes of<unk>  are not yet discovered or are not specifically known. But depending on some tests and data collected,<unk>  is thought to be caused by "both genetic and environmental" conditions or factors. SAHA syndrome is also taken in consideration among the sources that cause<unk> .
HAIR-AN syndrome
Kearns–Sayre syndrome
RIDDLE syndrome
Witteveen–Kolk syndrome
Schwartz–Matsuo syndrome
Michels Caskey syndrome
EAST syndrome
Fitzsimmons–Guilbert syndrome