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I bred an albino bristlenose with a super red bristlenose and all offspring were regular brown color. If I breed their offspring together (regular x regular) would i have a chance to get albinos and super reds in the offspring or do you think I'll only get regular browns again?
I'm hoping both the albino and super red genes are carried in such a cross.
Let me know what you guys think, thanks!

I don't know about getting both from a cross of the offspring because I never tried it. I do know that super red crossed back to one of the fry will produce both brown and super red. It should also hold true crossing albino to the brown fry will produce both albino and brown.

Larry

I see, that's cool. Do you think all of the offspring of the super red x albino cross hold those genes? If i select an offspring and then breed it back to the super red or albino (as you suggested), would that guarantee that i might get a few of the alternate color (ie. is the offspring always a carrier)?
Or is there a chance that the offspring x parent cross will not produce anything but regular browns again?

From what I've learned here about BN genetics (assuming I understand it correctly), all of your hybrid brown offspring from this first mating should be heterozygotes (carriers) for both the super-red color morph and for the albino color morph.

Therefore, if you wait for these hybrid brown offspring to grow up, and then you cross any of these hybrid brown offspring back to either one of the original parents, you should get a second generation of half super-red and half brown, or half albino and half brown (depending on which of the original parents you select as the mating partner).

Also, if you successfully perform either of the crosses listed above (hybrid brown x super-red, or hybrid brown x albino), then there's a 50% chance that the next generation of super-red offspring you get will also be carriers for the albino morph, and vice versa. Note - the statistical logic in this case is not flexible: There is a 50% chance that all the super-red or albino second generation offspring will be carriers of the opposite color morph, but this does NOT mean that 50% of these second generation offspring (from a single mating) will be carriers of the other color morph and 50% of them won't be carriers: Either all of them are carriers or none of them are, depending on the genetics of the particular brown parent you happened to use in this spawning.

Hi,

these simplified rules of Mendel only apply for traits that are controlled by a single locus and thus can be changed with a single mutation. For other cases the 50% rule does not apply.

For lutinism/albinism this premise is fulfilled (afaik), for the super reds I don't know.
It's just a gut feeling that this mutation might be more complex.

Cheers,

ok I'll see if i can breed some of the offspring back to the super red to see if i get super reds back. Thanks guys!

kamas88 wrote:these simplified rules of Mendel only apply for traits that are controlled by a single locus and thus can be changed with a single mutation. For other cases the 50% rule does not apply.

For lutinism/albinism this premise is fulfilled (afaik), for the super reds I don't know. It's just a gut feeling that this mutation might be more complex.

Yes indeed. I was under the impression that the super-reds are the result of a single simple recessive mutation, like many (all?) of the albinos (without getting into the subject that there are at least two different recessive mutations which can result in albinos, and not dealing with the idea of a double mutant albino as has been discussed in other forum threads ). Also, my assumption was consistent with the above comment by Larry:

pleco_breeder wrote:I do know that super red crossed back to one of the fry will produce both brown and super red.

Karsten, thank you for clarifying my post by adding these comments, because I was not careful in how I presented this info.

Cheers, Eric