Mitochondrial diseases are usually caused by mutation in mitochondrial DNA. These genes regulate different proteins synthesis, including carrier proteins and certain enzymes.
The replication of mitochondrial DNA follows binary fission. In this process, 1 set of genes would divide into 2 sets. The mitochondrial gene of children is inherited from their mother only. If there are any genetic defects or mutations in the mother’s mitochondrial DNA, it would be inherited by the children. If those changes in genes can cause mitochondrial diseases, the children have a 100% possibility of acquiring the diseases.
For the malate-oxaloacetate shuttle, 4 major genes are involved. They are PMDH1, MDH, PMDH2, mMDH1. PMDH-1 and PMDH-2 encode two different enzymes that provide NAD for the oxidation of malate. In addition, MDH and mMDH1 encode for an enzyme that directly oxidizes malate.