DNA Nomenclature

Dr. M.D. Jones mjones at crc.ac.uk
Fri Mar 4 10:34:53 EST 1994

Hi netters

I saw a message recently about Boehringer's M13 vectors and what
do you call the coding and non-coding strand.

In the past I have had numerous confused students asking for explanations.

Here is how I understand it (hopefully correct).

DNA (usually) is double stranded.
One DNA strand is identical in sequence to mRNA.  This is called the non-coding
strand or sense strand.
The other complementary strand is thus the coding strand or anti-sense strand.

I presume this comes about from the fact that the 'coding' strand acts the
template for the RNA polymerase to produce the mRNA.

Unfortunately to my mind, I find it logically to call it the reverse.  In that
the mRNA carries the coding information, and the DNA strand that is equivalent
to this should be the coding strand, but this is usually refered to as the

Confusing eh :-)

Due to the complementary nature of the double helix, I usually tell students
that DNA is double stranded and should be treated as such, and that calling the 
two DNA strands 'sense' and 'anti-sense' seems the most logical.

Mick Jones
RPMS, london, UK
mjones at rpms.ac.uk

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