Coffin Lowry Syndrome (CLS) is a rare genetic disorder that mostly affects males. It is caused by mutations in the RPS6KA3 gene, which provides instructions for making a protein that is necessary for the normal development of the brain and other body systems. However, there are some synonyms for CLS which are used by doctors and researchers. Some of these synonyms include Coffin Syndrome, Coffin Syndrome Type 1, Lowry Syndrome, and X-linked Mental Retardation with Craniofacial Abnormalities. These terms are used interchangeably to describe the same disorder and help doctors and researchers better understand and treat individuals with the syndrome.