Education Medicine

Difference between Mitochondrial and Nuclear DNA

Main Difference

The main difference between nuclear DNA and mitochondrial DNA is, nuclear DNA is the standard 46 chromosome containing DNA in which you inherit 23 chromosome from one parent and the rest 23 from another one. On the other hand, mitochondrial DNA contains just one chromosome, like a circular genome. This chromosome is much shorter and codes for proteins that are used in metabolic purposes. Another main difference is that mitochondrial DNA is only transmitted from mother and never from the father while nuclear DNA is inherited from both, mother and father.

Mitochondrial DNA

mitochondrial-dnaIt is found in the mitochondria of a cell. Mitochondrial DNA has only one chromosome which is comparatively shorter and they do not code for all the proteins but only specific proteins. This DNA make its own tRNA and even rRNA. It replicates separately from the nuclear DNA and is passed on to the progeny from mother only. That being the reason for which it does not undergo recombination. It is even read with a different genetic code from the nuclear DNA itself.

Nuclear DNA

nuclear-dnaUnlike mitochondrial DNA, nuclear DNA is found in every cell of the body. It consists of 46 chromosomes which are inherited from mother and father, both. The are comparatively longer with centromeres and telomers. DNA is composed of the adenine, thymine, guanine and cytosine which are the main nucleotides. DNA consists of a double helix chain, containing histones. This double helix strand is separated during division by various enzymes. The nucleotides are paired along the whole length of DNA, any change in the sequence of these nucleotides could prove very disturbing and alarming.

Key Differences

  • Mitochondrial DNA does not have histones while nuclear DNA does.
  • Mitochondrial DNA is circular while nuclear DNA is linear but both of them are double stranded.
  • Mitochondrial DNA is inherited from mother only while nuclear DNA from the parents.
  • Nuclear DNA is diploid and mt-DNA is in a state of ploidy.
  • In nuclear DNA the genes are arranged in the process of recombination. While mt-DNA is not changed during its transmission from mother to her off-spring.
  • Rate of mutation is higher in mt-DNA rather than nuclear DNA.
  • Mitochondrial DNA is also used for identification purposes.
  • Nuclear DNA has 46 chromosomes while mt-DNA has only 1.
  • The mitochondrial DNA make their own tRNA and rRNA.