APTX and hyperinsulinemic hypoglycemia, familial, 4: Although AOA1 affected individuals with mutations in APTX have been identified world wide; 13 individuals from 3 unrelated Tunisian family [6], 2 unrelated individuals from Germany [24], 3 unrelated Italian individuals [25], 2 American children [26] and 4 Caucasians with ataxia and CoQ10 deficiency [27], yet comprehensive screening by direct sequencing of the APTX gene did not identify any mutations in these 3 Saudi families.