a cytidine(6-4)thymidine in DNA = a cytidine-thymine dinucleotide in DNA
a cytidine(6-4)thymidine in dna = a cytidine-thymine dinucleotide in dna
a cytidine(6-4)thymidine in DNA = a cytidine-thymine dinucleotide in DNA
a cytidine(6-4)thymidine in dna = a cytidine-thymine dinucleotide in dna