Identify the DNA segment which is not a palindromic sequence.
(a) 5′ GGATCC 3′ (b) 5′ GAATTC 3′
3′ GGTACC 5′ 3′ CTTAAG 5′
(c) 5′ GCGGCCGC 3′ (d) 5′ CCCGGG 3′
3′ CGCCGGCG 5′ 3′ GGGCCC 5′
Answer (a) : Palindromic nucleotide sequence in the DNA molecule is the sequence of base pairs that reads same when orientation of reading is same, i.e., 5′ to 3′ on both strands or 3′ to 5′ on both strands. Hence, (a) is the correct answer, since it does not read same from both the sides.
