Number of genes in eucaryotic cells (E coli) 4.6Mb 4, 288 genes cerevisiae 13.5Mb 6,034 genes D. melanogaster 165Mb 12.000 genes C. elegans 97 Mb 19,099 genes H. Sapiens 3, 300 Mb 40,000 genes 28,000-34000 genes 25.947 genes Retroviruses 10 Kb about 10 genes28,000−34,000 genes 25,947 genes ( E. coli ) 4.6 Mb 4,288 genes S. cerevisiae 13.5 Mb 6,034 genes D. melanogaster 165 Mb 12,000 genes C. elegans 97 Mb 19,099 genes H. Sapiens 3,300 Mb 40,000 genes Number of genes in Eucaryotic cells Retroviruses 10 Kb about 10 genes