organellar DNA

The traits encoded by this type of DNA, in animals, generally pass from mother to offspring rather than from the father in a process called cytoplasmic inheritance. This is due to the ovum provided from the mother being larger than the male sperm cell, and therefore has more organelles, where the organellar DNA is found.{{cite journal | vauthors = Greiner S, Sobanski J, Bock R | title = Why are most organelle genomes transmitted maternally? | journal = BioEssays | volume = 37 | issue = 1 | pages = 80–94 | date = January 2015 | pmid = 25302405 | pmc = 4305268 | doi = 10.1002/bies.201400110 }}

Although maternal inheritance is most common, there are also paternal and biparental patterns of inheritance that take place.{{Cite journal| vauthors = Li Q, Wang X, Zhang J, Yao J, Duan D |date=2015-08-27|title=Maternal inheritance of organellar DNA demonstrated with DNA markers in crosses of Saccharina japonica (Laminariales, Phaeophyta) |journal=Journal of Applied Phycology|volume=28|issue=3|pages=2019–2026|doi=10.1007/s10811-015-0687-1 |s2cid=17827529}} The latter two patterns of inheritance are found most often in plants.

Recombination of organelle DNA is very limited, meaning that any traits that are encoded by the oDNA are likely to remain the same as they are passed from generation to generation.{{cite journal | vauthors = Birky CW | title = The inheritance of genes in mitochondria and chloroplasts: laws, mechanisms, and models | journal = Annual Review of Genetics | volume = 35 | issue = 1 | pages = 125–48 | date = December 2001 | pmid = 11700280 | doi = 10.1146/annurev.genet.35.102401.090231 }}

Unlike nuclear DNA, which is present as linear molecules inside the chromosomes, the entire genomes of chloroplasts and mitochondria are present on a single molecule of double-stranded circular DNA molecule; this is very similar structure to a bacterial chromosome.

Although the functionality and genetic structure vary significantly between different organelles and their host species, genetic characteristic patterns allow the differentiation between nucleolar and organellar DNA. A recently published machine-learning approach using only the genome sequences and multiple genome annotation tools can classify them.{{Cite journal |last1=Martin |first1=Roman |last2=Nguyen |first2=Minh Kien |last3=Lowack |first3=Nick |last4=Heider |first4=Dominik |date=2023-05-04 |editor-last=Birol |editor-first=Inanc |title=ODNA: identification of organellar DNA by machine learning |journal=Bioinformatics |language=en |volume=39 |issue=5 |doi=10.1093/bioinformatics/btad326 |issn=1367-4811 |pmc=10229373 |pmid=37195463}}

File:Mitochondrial DNA lg.jpg

File:Chloroplast DNA blank.svg

• Nuclear DNA
• Non-Mendelian Inheritance

{{Reflist|}}{{genetics-stub}}{{Nucleic acids}}

Category:DNA