Question

Which is the palindromic nucleotide sequence?
(i) GAATTC CTTAAG
(ii) AGGCCT TCCGGA
(iii) CAGTCG GTCAGC

• A. $i, ii$ and $iii$
• B. $i$ and $ii$
• C. $i$ only
• D. $i$ and $iii$

Answer 1

Answer: (B)

• The palindrome in DNA is a sequence of base pairs that reads same on the $2$ strands when orientation of reading is kept the same.
• For example, the following sequences reads the same on the $2$ strands in $5' - 3'$ direction. This is also true if read in the $3' - 5'$ direction.