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

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Chimpanzee Palindromes as a Percent of Entire Genome

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Human Palindromes as a Percent of Entire Genome

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Wild Boar Palindromes as a Percent of Entire Genome

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Horse Palindromes as a Percent of Entire Genome

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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