Pulex

... 23,000 genes. As JackBean said, viruses have the least number of genes in their genomes. And the one with most genes is a zooplankton, Daphnia pulex, with 31,000 genes; according to this news: http://www.physorg.com/news/2011-02-crustacean-genome-sequenced.html. The record for the most genes ...

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