What are the genetic changes related to Costeff syndrome ?
Mutations in the OPA3 gene cause Costeff syndrome. The OPA3 gene provides instructions for making a protein whose exact function is unknown. The OPA3 protein is found in structures called mitochondria, which are the energy-producing centers of cells. Researchers speculate that the OPA3 protein is involved in regulating the shape of mitochondria.  OPA3 gene mutations that result in Costeff syndrome lead to a loss of OPA3 protein function. Cells without any functional OPA3 protein have abnormally shaped mitochondria. These cells likely have reduced energy production and die sooner than normal, decreasing energy availability in the body's tissues. It is unclear why the optic nerves and the parts of the brain that control movement are particularly affected.