a group of mutations, known as mt-nd1, have been identified in mitochondrial dna. these mutations are associated with a number of debilitating diseases stemming
from the production of nonfunctional proteins in the mitochondria

The human mitochondrial DNA (mtDNA) is a double-stranded, circular molecule of 16 569 bp and contains 37 genes coding for two rRNAs, 22 tRNAs and 13 polypeptides. The mtDNA-encoded polypeptides are all subunits of enzyme complexes of the oxidative phosphorylation system.

Explanation:

the cell cycle is the final answer! : )