Why do you think your paper is highly cited?

The primary reason is that the IMPALA software package increases the functionality of the PSI-BLAST program, which was one of the topics of the paper: "Gapped BLAST and PSI-BLAST - A New Generation of Protein Database Search Programs," Altschul SF, Madden TL, Schaffer AA, Zhang J, Zhang, Z, Miller W, Lipman DJ, Nucleic Acids Research, Vol.25:3389-3402,1997, which has already been cited more than 5000 times.

  Does it describe a new discovery or new methodology that's useful to others?

It describes a new methodology for inferring a possible function of a protein from the 1-dimensional sequence of the protein.

  Could you summarize the significance of your paper in layman's terms?

PSI-BLAST starts with a single protein sequence and iteratively builds a mathematical model for what the sequences of similar proteins should look like. It is possible to quickly test a single PSI-BLAST derived model against a large database of new protein sequences to get a good idea of which new sequences fit the model. IMPALA offers a dual functionality of comparing a single new protein against a large database of PSI-BLAST constructed models.