 Mutations to "MUT" can be categorized as either "MUT0" (demonstrates no activity even in presence of excess AdoCbl), or "MUT1" (demonstrates very low activity in presence of excess AdoCbl).Over half of the mutations of "MUT" are missense mutations while nonsense mutations comprise a significant remaining fraction (approximately 14%)

Common treatment methods for MMA include a liver transplant or a liver and kidney transplant to combat the renal disease of methylmalonic acidemia.However, detrimental neurological effects can continue to plague patients even after a successful operation.