Bio::ASN1::EntrezGene is a regular expression-based Perl Parser for NCBI Entrez Gene genome databases [1]. It parses an ASN.1-formatted Entrez Gene record and returns a data structure that contains all data items from the gene record. [1] http://www.ncbi.nih.gov/entrez/query.fcgi?db=gene The parser will report error & line number if input data does not conform to the NCBI Entrez Gene genome annotation file format.