Biological and translational attributes of mitochondrial DNA copy number: Laboratory perspective to clinical relevance

Table 1 Key genes regulating mtDNA copy number

Gene	Role in mtDNA regulation	Associated disorders	Ref.
PGC-1α	Master regulator of mitochondrial biogenesis	Neurodegeneration, cancer, metabolic syndrome	[3,5,6]
TFAM	Maintains mtDNA integrity and replication	Mitochondrial diseases, aging	[5,9]
POLγ	Essential for mtDNA replication	MELAS, Kearns-Sayre syndrome, cancer	[88-90]
NRFs (1 and 2)	Coordinate expression of mitochondrial genes	Neurodegeneration, metabolic disorders	[3,5]

mtDNA: Mitochondrial DNA; PGC-1α: Peroxisome proliferator-activated receptor gamma coactivator 1-alpha; TFAM: Mitochondrial transcription factor A; POLγ: Polymerase gamma; NRFs: Nuclear respiratory factors; MELAS: Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes.