MTERFD1 belongs to the MTERF family which consists of four members including MTERF1, MTERF2, MTERF3 and MTERF4. Previous research showed that MTERFD1 is a mitochondrial protein that interacts with the mitochondrial DNA promoter region and decreases transcription initiation in mammalian mitochondria. This negative regulation is likely important for fine-tuning mitochondria transcription in response to physiological demands. Human mitochondrial transcription termination factor domain 1 (MTERFD1) was mutated in many types of cancer. In vivo and in vitro data indicated that MTERFD1 gene possesses oncogenic properties.