CRISPR technology shown to dial down gene activity in bacteria

In a series of experiments with laboratory-cultured bacteria, Johns Hopkins scientists have found evidence that there is a second role for the widely used gene-cutting system CRISPR-Cas9—as a genetic dimmer switch for CRISPR-Cas9 ...

Antibiotic resistance from random DNA sequences

An important and still unanswered question is how new genes that cause antibiotic resistance arise. In a new study, Swedish and American researchers have shown how new genes that produce resistance can arise from completely ...

DeepTFactor predicts transcription factors

A joint research team from KAIST and UCSD has developed a deep neural network named DeepTFactor that predicts transcription factors from protein sequences. DeepTFactor will serve as a useful tool for understanding the regulatory ...

New data on 'jumping genes' linked to cancer

Scientists from the University of Granada and GENYO have discovered a mechanism via which our cells protect themselves against these transposable or mobile genetic elements, known as "LINE-1," which are involved in the development ...

page 1 from 40

DNA sequence

A DNA sequence or genetic sequence is a succession of letters representing the primary structure of a real or hypothetical DNA molecule or strand, with the capacity to carry information as described by the central dogma of molecular biology.

The possible letters are A, C, G, and T, representing the four nucleotide bases of a DNA strand — adenine, cytosine, guanine, thymine — covalently linked to a phosphodiester backbone. In the typical case, the sequences are printed abutting one another without gaps, as in the sequence AAAGTCTGAC, read left to right in the 5' to 3' direction. Short sequences of nucleotides are referred to as oligonucleotides and are used in a range of laboratory applications in molecular biology. With regard to biological function, a DNA sequence may be considered sense or antisense, and either coding or noncoding. DNA sequences can also contain "junk DNA."

Sequences can be derived from the biological raw material through a process called DNA sequencing.

In some special cases, letters besides A, T, C, and G are present in a sequence. These letters represent ambiguity. Of all the molecules sampled, there is more than one kind of nucleotide at that position. The rules of the International Union of Pure and Applied Chemistry (IUPAC) are as follows:

This text uses material from Wikipedia, licensed under CC BY-SA