Abstract: The present invention is directed to the use of at least one secondary subunit sequence that varies from a primary subunit sequence by the addition, deletion and/or substitution of at least one subunit for inferring information about the primary subunit sequence. The invention is also directed to the use of such variant sequences for wholly or partially executing a task on an primary subunit sequence, which in one embodiment is refractory to the execution of that task and more particularly to the use of such sequence(s) for wholly or partially deducing the sequence of a primary subunit sequence. In a preferred embodiment of the present invention, the variant sequences are generated by mutagenesis techniques. The subject invention further relates to a method, which is optionally implemented by a processing system, for designing secondary subunit sequences.