Genome, mitochondrial

All of the genetic information contained in the chromosome of the mitochondrion, a structure located in the cytoplasm outside the nucleus of the cell.

The nucleus houses the better known chromosomal genome, our complement of chromosomes.

The mitochondrial genome consists of mitochondrial DNA (abbreviation: mtDNA).

Mitochondrial DNA has several unusual features.

It is a circular molecule, unlike the linear molecule of DNA in a nuclear chromosome, and it has a far more limited repertory of genes than nuclear DNA.

And, last but not least remarkable, mitochondrial DNA (mDNA) is transmitted to the offspring only by the mother.

(The sperm has no mitochondria.) By contrast, the chromosomes in the nucleus are transmitted in equal part by both parents to the child.

Together, the mitochondrial genome and the nuclear chromosomal genome constitute the entire human genome.