DNALAB, a comprehensive software package dedicated to aiding recombinant DNA research, has been developed. This package contains, in addition to standard options available in related software, several unique features for sequence analysis. One of the options allows a researcher to identify the restriction enzyme sites closest to a given range of sequence, where the enzymes generate an easily separable fragment that includes the range. Another option enables one to analyze potential splice sites in a gene sequence, delete the hypothetical introns, and analyze the mRNA sequences possible from such splicing.