We detected a heterozygous MMACHC gene mutation (c.656_658delAGA, p.K220del, OMIM# 277400) in P74 and a heterozygous MMACHC gene nonsense mutation (c.609G>A, p.W203*, OMIM# 277400) in P75 who previously bore a child with Methylmalonic Acidemia. Here, MMACHC is linked to methylmalonic acidemia.