Question

If you have normal Leopard Geckos (genotype: LL) and you found the patternless Leopard Gecko (genotype: II) in the wild for the very first time, and you wanted to produce this phenotype in captivity to introduce it to

the pet trade, what crosses would you need to do in order to produce a phenotypic patternless in captivity for the first time?

Answer 1

To introduce the patternless phenotype of Leopard Geckos into captivity, conduct a cross between a normal Leopard Gecko (LL) and a patternless one (II), followed by crossing two F1 heterozygous (LI) geckos. Use Punnett squares to predict genotypic and phenotypic ratios, and perform test crosses for genotype verification.

Step-by-step explanation:

To produce the patternless phenotype in Leopard Geckos (genotype II) in captivity, you would initially cross a normal Leopard Gecko (genotype LL) with a patternless Leopard Gecko (genotype II). Assuming that the patternless trait is recessive, the first generation (F1 generation) would all be heterozygous (LI) and display the normal pattern. To produce a patternless Gecko, you would then cross two F1 heterozygous geckos (LI x LI).

Using a Punnett square, we can predict that this cross would result in a genotypic ratio of 1:2:1, consisting of LL (normal), LI (normal, carrier of patternless), and II (patternless) genotypes. The phenotypic ratio would be 3 normal to 1 patternless. This cross would be the first time patternless geckos could be produced in captivity. You could then continue to perform test crosses to determine the genotypes of individuals that exhibit the dominant trait but may carry the recessive patternless allele.