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Centromere

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A centromere is a constricted region of a chromosome that separates it into a short arm (p) and a long arm (q). During cell division, the chromosomes first replicate so that each daughter cell receives a complete set of chromosomes. Following DNA replication, the chromosome consists of two identical structures called sister chromatids, which are joined at the centromere.

Centromere.jpg

Public domain logo This image is taken from the Talking Glossary of Genetic Terms and is reproduced courtesy of the National Human Genome Research Institute.

Centromere locations (Build 37)

The information in this table was extracted by Kitty Cooper from: http://genome.ucsc.edu/cgi-bin/hgTables Instructions were taken from: http://www.biostars.org/p/2349/. Note that the positions in Kitty's chart differ from those provided by Family Tree DNA which we are informed currently uses Build 36. See the FTDNA FAQ Where are the centromeres located on each autosomal DNA chromosome.

Chromosome Start Stop
1 121535434 124535434
2 92326171 95326171
3 90504854 93504854
4 49660117 52660117
5 46405641 49405641
6 58830166 61830166
7 58054331 61054331
8 43838887 46838887
9 47367679 50367679
10 39254935 42254935
11 51644205 54644205
12 34856694 37856694
13 16000000 19000000
14 16000000 19000000
15 17000000 20000000
16 35335801 38335801
17 22263006 25263006
18 15460898 18460898
19 24681782 27681782
20 26369569 29369569
21 11288129 14288129
22 13000000 16000000
X 58632012 61632012

Reporting segments crossing the centromere

Family Tree DNA does not count the centiMorgans in the centromere. They allow for a block to continue across the centromere so that if the block on the left is A, the centromere is B, and the block on the right is C, then the matching segment is reported as A+C.[1]

Further reading

Scientific papers

References

  1. Canada R. Message posted in the Family Tree DNA Forums, 27 March 2014. As of 3 June 2016 the out-of-date FAQ. How does the Family Finder program account for the centromere? in the FTDNA Learning Center has not been updated.


Public domain logo

This article uses material in the public domain from the Talking Glossary of Genetic Terms and is reproduced courtesy of the National Human Genome Research Institute.