Lavender

[gargoyle]

I was wondering what morphs go into creating lavenders, and are they co-dominant, dominant or recessive genes. I've managed to get my head around some of the morphs and am moving onto the more difficult ones. Thankyou for any help.

 

[Clint Boyer]

Lavender is one single recessive mutated gene. It acts just like any other single recessive, breed it to a normal and get normals het Lavender. Cross those offspring or back the the Lavender to produce snakes homozygous for Lavender.

 

[gargoyle]

What about a snow, my female is a snow, and I'm getting a male lavender. So they are all recessive genes, yes? So I would get a mix of all then?

 

[Serpwidgets]

A snow is homozygous for both amel and anery (which are both simple-recessive) so if you were to cross a snow to a lavender you would get normals that were (triple) het for lavender, anery, and amel.

---

If you were to cross those hets to each other, each trait would reappear in about 25% of the offspring, meaning (statistically) 1 in 16 would be snow. The same odds would be present for opals (amel lavender) and the "anery lavender" combination.

Overall, there's a 1 in 64 (1/4 X 1/4 X 1/4) chance per egg that it would be homozygous for all three traits.

---

If you were to cross the offspring back to the snow, each trait would have a 50/50 chance of appearing in any offspring. So overall, the odds would be equal for any hatchling to be normal, amel, anery, or snow.

---

If you were to cross the offspring back to the lavender, about half of the clutch would then express lavender.

 

[gargoyle]

If they're all recessive genes, then how do they become dominant when you pair them up?

 

[Serpwidgets]

Recessive genes do not become dominant.

At each locus (for example, the lavender locus) an individual receives one copy from mom, one copy from dad.

Start by crossing a lavender to a normal:

If the normal parent is just a normal, the offspring get one L⁺ (Normal) gene from that parent.

Meanwhile, the lavender parent contributes one l^l (lavender mutant)

These offspring then have a genotype of L⁺ · l^l and since the lavender gene is recessive, the normal gene is the only one expressed. So, the offspring look normal, but they are heterozygous because they have two different genes at this locus.

When you cross two of them together, each parent creates sperm or egg cells, and each sperm or egg cell contains only one of those two genes... each sperm can be either L⁺ or l^l and each egg can be either L⁺ or l^l.

As a result, there are four possible outcomes for any given baby:

It gets a L⁺ sperm with a L⁺ egg, and it is normal.

It gets a l^l sperm with a L⁺ egg, and it is normal. (but het for lavender)

It gets a L⁺ sperm with a l^l egg, and it is normal. (but het for lavender)

It gets a l^l sperm with a l^l egg, and it is lavender (because there is no normal gene present in this animal.)

(This is what the four squares in a simple Punnett square represent.)