1. Citations
A Study on the Frequency and Location of Palindromic DNA
across 41 Mammalian Genomes
Devin Petersohn1 and Chi-Ren Shyu (Mentor)1,2
1Department of Computer Science, College of Engineering, 2MU Informatics Institute, University of Missouri
0.00%
0.02%
0.04%
0.06%
0.08%
0.10%
0.12%
0.14%
0.16%
0.18%
0.20%
0.22%
0.24%
1 2A 2B 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 X Y
Percentofchromosome
Chromosome number
Chimpanzee Palindromes as a Percent of Entire
Genome
AT TA CG GC
0.00%
0.02%
0.04%
0.06%
0.08%
0.10%
0.12%
0.14%
0.16%
0.18%
0.20%
0.22%
0.24%
1 2B 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 X Y
Percentofchromosome
Chromosome number
Human Palindromes as a Percent of Entire Genome
AT TA CG GC
0.00%
0.02%
0.04%
0.06%
0.08%
0.10%
0.12%
0.14%
0.16%
0.18%
0.20%
0.22%
0.24%
1 2B 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 X Y
Percentofchromosome
Chromosome number
Wild Boar Palindromes as a Percent of Entire Genome
AT TA CG GC
0.00%
0.02%
0.04%
0.06%
0.08%
0.10%
0.12%
0.14%
0.16%
0.18%
0.20%
0.22%
0.24%
1 2B 3 4 5 6 7 8 9 10111213141516171819202122232425262728293031 X
Percentofchromosome
Chromosome number
Horse Palindromes as a Percent of Entire Genome
AT TA CG GC
What is a Palindrome?
Palindrome Locations and Frequencies are not Random
A Palindrome is a word that spells itself
backwards. For example:
racecar
Spelled backwards, racecar spells racecar,
therefore it is a palindrome.
In DNA, palindromes are patterns that are
read the same way forwards and
backwards. Because DNA is double
stranded, however, palindromes within
DNA are different than palindromes in
language. For example:
5’ 3’
DNA is read from 5’ to 3’ on each strand. It
also pairs such that A pairs with T and C
pairs with G. If we were to look at both
strands together, they would look like this:
5’ 3’
3’ 5’
If you read the bottom strand from 5’ to 3’,
it is the exact same as the opposite strand.
Thus, a palindrome is a sequence that is its
own reverse complement.
Percent of Palindromes Based on Center Base Pairs Why Study Palindromes?
Acknowledgements
• Palindromes have been shown to form
interesting structures in DNA.
• Hairpin Structures:
• Cruciform Structures:
• Palindromes have also been shown to be
involved in certain diseases and cancers.
• The mutation rate within “almost”
palindromes has been shown to be 300x
the normal mutation rate.
• These sequences are strongly
selected toward being
palindromic
• Palindromes have also been shown to
have regulatory functions, and also have
functions within binding sites.
[1] Glickman, Barry W., and Lynn S. Ripley. "Structural intermediates of deletion mutagenesis: a role for palindromic DNA." Proceedings of
the National Academy of Sciences 81.2 (1984): 512-516.
[2] Tanaka, Hisashi, et al. "Large DNA palindromes as a common form of structural chromosome aberrations in human cancers." Human
cell 19.1 (2006): 17-23.
This Project was funded by the MU Engineering Undergraduate Honors Scholar in Research Program