In this week's Science, a team led by Harvard University researchers reports on a study in zebrafish that provided new insights into how melanoma is triggered. The investigators focused on crestin, a gene that is expressed in embryonic neural crest cells, but not adult tissues — except when melanoma develops. They found that the cancer occurs when a series of genes upstream of crestin enhanced its expression and restarting the neural crest cell program that normally occurs only during embryonic development. The findings may point to a new approach for detecting and possibly preventing melanoma initiation.
Also in Science, a team of US and French investigators demonstrates that the overexpression of two genes from the Y chromosome on the X chromosome could preserve the ability to reproduce in male mice lacking the Y chromosome. The mice lacking the Y chromosome had abnormal testes and sperm, but inducing expression of the genes on their X chromosomes allowed their sperm to proliferate. Using artificial fertilization, the team was able to use the sperm from nine of 13 mice to produce offspring. The results, the authors note, support the existence of functional redundancy between Y chromosome genes and their homologs encoded on other chromosomes.