Genetic Crosses With Sex Linked Traits
In J.R.R Tolkien’s The Lord of the Rings, the Black Riders of Mordor ride steeds with eyes of fire. As a geneticist, you are very interested in the inheritance of the fire-red eye colour. A discovery is made that the eyes contains two types of pigments, brown and red, that are usually bound to core granules in the eye. In wild-type steeds, precursors are converted by these granules to the above pigments, but in steeds homozygous for the recessive X-linked gene w (white eye), the granules remain unconverted and a white eye results. The metabolic pathways for the synthesis of the two pigments are shown in the attached file. Each step of the pathway is controlled by a gene: mutation v results in vermillion eyes; cn results in cinnabar eyes; st results in scarlet eyes; bw results in brown eyes; and se results in black eyes. All these mutations are recessive to their wild-type alleles, and all are unlinked. For the following genotypes, show the proportions of steed eye phenotypes that would be obtained in the F1 of the given matings.
This case is answered.