Nucleic acid sequence

The nucleotide base sequence, or the sequence of nucleotides of a nucleic acid.

In the notation, the first letter of their designations are used for the nucleotide bases of the nucleotides: adenine A, guanine G, thymine T uracil U and cytosine C. The deoxyribonucleic acid ( DNA) are present, the four bases adenine, guanine, thymine and cytosine, in RNA, adenine, guanine, uracil and cytosine.

According to convention, the nucleotide sequence is read from the 5 ' end to the 3' end of the strand in the same direction in which the polymerase, the synthesized nucleic acid.


A nucleotide sequence of DNA is determined by DNA sequencing. Nucleotide sequences of DNA are stored among other large public sequence databases such as GenBank.

Statistical Analysis

The presentation as a symbol sequence, the DNA can be examined statistically good. It may, for example, the frequency of so-called n-tuple, that is, the occurrence of part words of the length n to be examined. So immersed in the human genome on average, the episode " CG" significantly lower than for all other 2- words. The local frequency distributions of various Nukleotidwörter can first clues to the functions of certain DNA segments give ( CpG islands, stop codons sequence ends of introns ).