A collaborative study between University of Edinburgh and University of Bath researchers has revealed how black-and-white cats, and some horses, develop their distinctive piebald patches in the womb. The insights could help scientists better understand medical conditions that occur early on in development, such as those stemming from cells forming improperly during embryo development.

Previous researchers discovered that pigment cells in mice move and multiply in a random manner during early development, which contradicts recent theories that animal piebald patterns form due to the slow movement of pigment cells that prevents them from reaching the embryo.

The current study used the same mathematical model as the previous research to better understand the conditions that affect cell positioning and these effects on piebald patterns.

''We already know cells move through the developing skin to create pigment," Richard Mort, who participated in the research, said in a press release. "We have discovered that they move and multiply at random which is not what was expected. Using a mathematical model we were then able to show that this simple process could explain piebald patterns.''

Christian Yates, a mathematical biologist who collaborated with Mort, claims that piebald patterns are caused by a faulty gene kit, but not because cells are slowed down during development - he claims it's due to a reduction in their multiplication rate.

"Previously it was thought that the defective kit gene slowed cells down but instead we've shown that it actually reduces the rate at which they multiply," he explained. "There are too few pigment cells to populate the whole of the skin and so the animal gets a white belly. In addition to kit, there are many other genes that can create piebald patterns, the mathematical model can explain piebald patterns regardless of the genes involved.''

The study was published in the Jan. 6 issue of Nature Communications.