Human gene changes color of fish

Scientists have changed mutated yellow zebrafish to a yellowish white standard fish with dark stripes, by inserting the pigmentation genes into fry.

In an interesting "trick", they found that when inserting a similar type of human pigment gene for fish, they also turned the same color.

As with humans, zebrafish skin color is determined by pigment cells, containing pigment particles called melanosomes. The amount, size and darkness of melanosome particles in each pigment cell will affect its skin color. For example, Europeans have fewer melanosomes, which are smaller and lighter than the West African strains, while Asians lie somewhere between these two groups.

Yellow zebrafish fish have fewer, smaller and lighter melanosome pigment particles than normal fish.

Experiment

Keith Cheng of Pennsylvania State Medical University and colleagues found that the mutation of a gene (causing it to malfunction) made the zebrafish body not produce the protein needed to make pigment particles.

" A gene mutation causes the protein maker to stop ," Cheng said.

But when Cheng's group inserted an error-free version of the gene into 2-day-old yellow zebrafish embryos, they produced melanosome, making dark skin color familiar in just a few days.

Next, the team explored HapMap, an online data on human gene records, and found that there was a similar gene for melanosome production on our bodies. Therefore, they inserted this gene into yellow zebrafish embryos, and they also returned to the familiar dark color.

" We surmised that zebrafish skin was darker due to the similar function of the transplanted human gene - genes that produce more, larger and darker melanosome particles, " Cheng said.

Mutations in humans

It seems like yellow zebrafish, light-skinned Europeans also have a mutation in the melanosome gene, resulting in less pigmentation in their skin color. Scientists speculate that the diversity of this gene could also be the cause of blue-eyed and light-colored hair in some people.

However, Cheng said, it is important that the study showed that mutations in humans and zebrafish are different - while genes in zebrafish fail completely in protein production to produce melanosome, mutant genes in people still work, only things are not positive.

This finding may lead to advances in the targeting of malignant melanoma, or in studies of how to alter skin color without the use of chemicals or other damaging solutions.

Thuan An