Question

Our genetic material, DNA, is formed from a 4 letter alphabet" of bases: A, T, G, C (adenine, thymine, guanine, and cytosine). The order in which the letters are arranged is important, but because a molecule can move, there is no difference between a sequence and the same sequence reversed. How many distinct DNA sequences of 5 bases are there?

Answer 1

544 distinct DNA sequences are there.

Step-by-step explanation:

DNA contains four nitrogenous bases adenine, thymine, guanine and cytosine.

Total DNA sequences of 5 bases are
`4^(5)`

= 1024 sequences.

Out of 1024 sequence,
`4^(3)` sequence is palindromic sequence (the sequence that can be determined only if the first three sequences are known.

64 sequences are palindromic sequence.

Since, the difference between the sequence and the same sequenced reverse is zero. 960 sequences (1024-64) are reverse of the other 959 sequences.

Distinct DNA sequences can be calculated by:

Distinct DNA sequence = Palindromic sequence + 1/2 (remaining sequences)

= 64+1/2(960)

=544 sequences.

Thus, the distinct DNA sequences are 544.