TCN2 and hyperinsulinemic hypoglycemia, familial, 4: The remaining 59 (deemed “MMA_Other” in the following sections) had other causes of MMA, namely, acyl‐CoA synthetase deficiency (20 cases), succinyl‐CoA ligase deficiency (three cases), transcobalamin 2 (TCN2) deficiency (three cases), cblA‐type MMA (two cases), cblB‐type MMA (one case), and unspecified MMA (30 cases) [7].