The Cambridge Reference Sequence (CRS) for

human Humans (''Homo sapiens'') or modern humans are the most common and widespread species of primate, and the last surviving species of the genus ''Homo''. They are Hominidae, great apes characterized by their Prehistory of nakedness and clothing ...

mitochondrial DNA Mitochondrial DNA (mtDNA and mDNA) is the DNA located in the mitochondrion, mitochondria organelles in a eukaryotic cell that converts chemical energy from food into adenosine triphosphate (ATP). Mitochondrial DNA is a small portion of the D ...

was first announced in 1981. A group led by

Fred Sanger Frederick Sanger (; 13 August 1918 – 19 November 2013) was a British biochemist who received the Nobel Prize in Chemistry twice. He won the 1958 Chemistry Prize for determining the amino acid sequence of insulin and numerous other prot ...

at the

University of Cambridge The University of Cambridge is a Public university, public collegiate university, collegiate research university in Cambridge, England. Founded in 1209, the University of Cambridge is the List of oldest universities in continuous operation, wo ...

had sequenced the mitochondrial genome of one woman of European descent during the 1970s, determining it to have a length of 16,569 base pairs (0.0006% of the nuclear human genome) containing some 37 genes and published this sequence in 1981. Due to a mistake the actual length of it is 16,568. When other researchers repeated the sequencing, some striking discrepancies were noted. The original published sequence included eleven errors, including one extra base pair in position 3107del (it was C, but now it is N), and incorrect assignments of single base pairs. Some of these were the result of contamination with bovine and

HeLa HeLa () is an immortalized cell line used in scientific research. It is the oldest human cell line and one of the most commonly used. HeLa cells are durable and prolific, allowing for extensive applications in scientific study. The line is ...

specimens. The corrected revised CRS was published by Andrews et al. in 1999. (The original nucleotide numbering was retained to avoid confusion.) The reference sequence belongs to European haplogroup H2a2a1. The revised CRS is designated as rCRS. It is deposited in the GenBank NCBI database under accession number NC_012920.''Homo sapiens'' mitochondrion, complete genome
"Revised Cambridge Reference Sequence (rCRS): accession NC_012920"
''

National Center for Biotechnology Information The National Center for Biotechnology Information (NCBI) is part of the National Library of Medicine (NLM), a branch of the National Institutes of Health (NIH). It is approved and funded by the government of the United States. The NCBI is lo ...

''. Retrieved on 30 January 2016. When mitochondrial DNA sequencing is used for genealogical purposes, the results are often reported as differences from the revised CRS. The CRS is a reference sequence rather than a record of the earliest human mtDNA. A difference between a tested sample and the CRS may have arisen in the lineage of the CRS or in the lineage of the tested sample. The CRS includes seven nucleotides that are rare polymorphisms: 263A, 311C-315C, 750A, 1438A, 4769A, 8860A, and 15326A. An alternative African (Yoruba) reference sequence has also been used sometimes instead of the Cambridge. It has a different numbering system with a length of 16,571 base pairs and represents the mitochondrial genome of one African individual. Other alternative reference sequences that have also sometimes been used include the African (Uganda), Swedish and Japanese sequences. In 2012, it was proposed that the revised Cambridge Reference Sequence (rCRS), should be replaced by a new Reconstructed Sapiens Reference Sequence (RSRS). The RSRS keeps the same numbering system as the CRS, but represents the ancestral genome of

Mitochondrial Eve In human genetics, the Mitochondrial Eve (more technically known as the Mitochondrial-Most Recent Common Ancestor, shortened to mt-Eve or mt-MRCA) is the matrilineal most recent common ancestor (MRCA) of all living humans. In other words, she ...

, from which all currently known human mitochondria descend. The RSRS should be more useful for comparing the changes in different haplogroups although this has been debated.{{cite journal , vauthors=((Bandelt H-J)), Kloss-Brandstätter A, Richards MB, ((Yao Y-G)), Logan I , title=The case for the continuing use of the revised Cambridge Reference Sequence (rCRS) and the standardization of notation in human mitochondrial DNA studies, journal=Journal of Human Genetics, date=5 December 2014, volume=59, issue=2, pages=66–67, doi=10.1038/jhg.2013.120, pmid=24304692, s2cid=21995571, doi-access=free

Family Tree DNA FamilyTreeDNA is a division of Gene by Gene, a commercial genetic testing company based in Houston, Texas. FamilyTreeDNA offers analysis of autosomal DNA, Y-DNA, and mitochondrial DNA to individuals for genealogical purpose. With a database ...

reports results for mtDNA for both rCRS and RSRS.

References

External links

GenBank record of the revised Cambridge Reference Sequence (rCRS)

Genetic genealogy Genetics in the United Kingdom category:History of genetics Human mitochondrial genetics Human mtDNA haplogroups Science and technology in Cambridgeshire