Researchers have discovered that the genetic malfunction that causes a form of mental retardation called Noonan Syndrome (NS) produces an imbalance in the genesis of two types of cells in the developing embryonic brain.

Researchers have discovered that the genetic malfunction that causes a form of mental retardation called Noonan Syndrome (NS) produces an imbalance in the genesis of two types of cells in the developing embryonic brain. NS is a relatively common genetic disorder, occurring in one of every 2,500 live births. It is characterized by congenital heart defects, short stature, learning disabilities, and mental retardation. Approximately 50% of NS cases are caused by a genetic mutation in a biochemical switch called SHP-2. SHP-2 is involved in molecular pathways regulating development of brain cells. The NS mutations cause SHP-2 to be constantly activated.