What are the chances of Coffin-Lowry Syndrome being inherited?

This condition is inherited in an X-linked dominant pattern. A condition is considered X-linked if the mutated gene that causes the disorder is located on the X chromosome, one of the two sex chromosomes. The inheritance is dominant if one copy of the altered gene in each cell is sufficient to cause the condition. In most cases, males (who have one X chromosome in each cell) experience more severe signs and symptoms of the disorder than females (who have two X chromosomes in each cell). A striking characteristic of X-linked inheritance is that fathers cannot pass X-linked traits to their sons.

Between 70 percent and 80 percent of people with Coffin-Lowry syndrome have no history of the condition in their families. These cases are caused by new mutations in the RPS6KA3 gene. The remaining 20 percent to 30 percent of affected individuals have other family members with Coffin-Lowry syndrome.