Reptile & Amphibian Forums

I see het (heterozygous) for translucent(trans) and hypomelanistic (hypo) a lot but wonder if what I know is correct since it does not match some adds with the genetics and pictures of parents posted.
This is my understanding of genetics but by what I see others selling I might be wrong or mis understand.
Breeding a:
normal dragon x normal dragon= all babies are normal

normal dragon x het dragon (either hypo or trans)= 50% are het and 50% are normal. I would call them all possible het since you have to prove out each individual dragon and can not tell by looking at the dragon.

het dragon (either hypo or trans) x trans or hypo dragon = 50% of offspring are het and 50% are either trans or hypo.

het dragon x het dragon = 25% normal, 25% show the trait (either trans or hypo), 50% are 100% het.
Those that appear normal are referred to as 66% possible het. There is a 2 in 3 chance they carry the recessive gene for either trans or hypo.

So since you can not tell possible het from a 100% het I would call them all possbile het since each dragon individually has to be proven out.

Am I correct or am I wrong. So many people seem to have different opinions but from research and genetics this is what I figure.
Thanks!!
Sizzlin Dragons

You are partly correct.

The het to normal dragon results are true for all recessive traits. However when you match two het animals together with the same trait (ie both het for hypo, assuming hypo is a simple recessive trait) you would have 25% normal, 50% het and 25% visible morph. (ie visible hypo). Out of the three normal looking dragons, each would be 66% possible het.

However if you mix two het animals for two different traits, things get more complicated. As the traits which cause each morph in animals are often on different alleles or parts of the DNA strand, so not all the offspring will have both hets present.

Crossing a het hypo and a het trans, will result in 25% normal, 25% het for trans, 25% het for hypo and 25% het for hypo and trans. Each baby will have a 75% possible het to be het for trans or hypo, and 25% chance of het for both.

Its much better to cross like to like, than two different recessive traits, unless you are going for double recessive traits, though its better to start with visual morph of one or both traits in the parents. Such as crossing a trans to a hypo.

I am no expert in genetics, far from it, but the above is how I understand mixing recessive traits. Adding in co-dominate and dominate (besides normal) together does have different results. The more traits being combined the more complex the results. Also, the percentages are abstract. Each egg has that chance, not the clutch, so its possible to have a 16 egg clutch from a normal x het breeding produce all normal offspring or all hets instead of the expected 50% het. There just is no way to tell by looking at the offspring.

Also keep in mind I am not 100% certain if hypo and trans are both recessive traits. If either is co-dominant or dominate, the results will be totally different.

The site below is a good basic reference to genetics, though it focuses on corn snake genetics. However the basic principals apply to all reptiles exhibiting similar recessive traits.

www.vmsherp.com/LCGenetics101.htm
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PHLdyPayne