Figure 9.

Variation in estimated total cone photoreceptor number and estimated total horizontal cell number in the C57BL/6J and A/J strains of mice, and in 26 recombinant inbred strains of mice derived from these same parental lines. While the A/J strain has the lowest number of both cones and horizontal cells, and C57BL/6J has 70% more cones and nearly 90% more horizontal cells, there is little correlation between them across the recombinant inbred strain-set. Both traits must be controlled by numerous genetic variants modulating developmental processes affecting cell number, and that do so for each population largely independently.