EBJD= a full fledged, purebred, electric blue dempsey.
blue gene= half EBJD, half regular jack, it carries the gene for electric blue(heterozygous), but it isnt expressed.
Blue gene jack dempsyes carry the ressesive trait that causes the electric blue color but because its a ressecive trait its not shown in the " carrier " of the gene
So blue gene carrier looks normal but if paired with another blue gene carrier it could produce electric blue offspring and EBJD means an actual electric blue jack dempsy