In article <328B53C8.167E at pasteur.fr>, hbadrane at pasteur.fr says...
>>Hi dear Netters,
>>I 'm looking for a software (mac, dos, unix) which from an alignement of
>sequences, gives three alignements each corresponding to the three
>positions in the codons.
You could take a look at SeqSearch v1.0 for Windows, one of the methods in the
package will do the thing you asked for.