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Non- Mendelian inheritance such as extra nuclear inheritance or cytoplasmic inheritance was first discovered in 1908 by Carl Correns with the plant called Mirabilis Jalapa. Later research revealed that DNA present in chloroplast and mitochondria were responsible for the unusual inheritance pattern observed in Mirabilis Jalapa and various other organisms.

The extra nuclear pattern of inheritance has various practical applications. The phenomenon of heterosis was identified by plant breeders for many years that the progeny from a specific cross can produce more yield than either of the two parents utilized. That is, phenotype of the progeny is of greater economic value than either of the two parents involved. The practical application of heterosis has been largely facilitated in crop plants by the utilization of cytoplasmic male sterility for inexpensive, extensive emasculation of the parents of hybrid seeds. This technique is currently utilized in commercial production of hybrid agricultural commodities such as corn, onions, sorghum, and petunias, sugar beets and so on.

When genes of the organelles within a species are inherited from a single parent they can be utilized in tracing the ancestry of the individual as there is no crossing over or recombination. Evolutionary studies in Algae and Plants are carried out utilizing the chloroplast genes.

A number of hereditary diseases in humans have been known to be caused by mutations in mitochondrial genes. Mitochondrial genes are also utilized to trace the female ancestor of humans, as the Y-chromosomal genes can be utilized to trace male ancestors. By this means, differences among males and females in patterns of reproduction or migration are analysed.

Mitochondrial genes are also utilized in studies of animal behaviour to recognize the parents of animals and birds and establish their social organization. The organelle genome such as mitochondrial DNA or chloroplast DNA are simple than nuclear DNA, it can be extracted and analysed from very old or poorly conserved samples.