Palindrome - A double strand DNA locus whose 5'-to-3' sequence is identical on each DNA strand. The sequence is the same when one strand is read left to right and the other strand is read right to the left.
Alternatively looking on one strand of the DNA the definition for palindrome is:
A region of sequence, that when it’s been read left to right it is complementary to the sequence that been read right to left (A match T, and C match G).
In molecular biology the definition we gave for palindrome is “too exact”, therefore being of little use. Palindromes that matter are “approximate” which can contain a certain number of mismatches and allowed a gap region between the inverted repeats.
Important biological roles
Palindromes have many important biological roles, some of been used in transcription termination, transcription-binding sites, restriction enzymes and gene amplification.
Here are some well-known examples in biology, for palindromes uses: