Embryos carrying two copies of the nonfunctional gene fail to develop kidneys.
Dr. Jordan Kreidberg, a postdoctoral fellow in the Jaenisch laboratory at the Whitehead Institute, explains that WT-1 is a member of a class of genes known as tumor suppressor genes. Scientists believe that tumor suppressor genes work in a variety of different ways to help regulate growth and development in normal cells. Tumors occur when a mutation somehow prevents such a gene from performing its normal regulatory function. Cancer develops in these children when some event disrupts the one normal copy of the gene in a single kidney cell, and as a result the cell grows out of control, producing a tumor. Studies of tumor suppressor genes in animal models offer new opportunities to understand the molecular basis of growth and development in health and disease.