[Roms]

I should see him this weekend and I'll take some pictures to post. His female EB is very nice, I'll try to find out more information on where he got his facts...


---------------------------

I talked with my friend and the Electric Blue Jack Dempsey is a recessive gene. I found a thread the sums it up better than I could:

If we assumed the 'BJD' was the same as a recessive albino, and use the code 'bb' for BJD and 'NN' for normal JD, we would get :-

bb x NN = 100% fry bN (normal looking but carrying the 'blue' gene)

we then cross

bN x bN = 25% bb (blue dempseys), 50% bN (normal looking but carrying the 'blue' gene), 25% NN (normal JD)

we then cross

bN x bb = 50% bb, 50% bN

Now this seems straight forward, and would be if the 'blue' gene was a simple recessive, but I don't think it is. From what I've read, 2 doses of blue gene is fatal (like Manx cats) or at best the fry only survive for a short while. From my own experience I've found all the fish I have had to be males and of low or total sterility, this leads me to think the gene is also sex linked in some way. I also think it has other physiological effects, or, the blue colour is an incidental by-product of another gene's malfunction. Either way, I'm sure the geneticists would have fun with these !

Resource