What are the genetic changes related to microcephaly-capillary malformation syndrome ?
Microcephaly-capillary malformation syndrome results from mutations in the STAMBP gene. This gene provides instructions for making a protein called STAM binding protein. This protein plays a role in sorting damaged or unneeded proteins so they can be transported from the cell surface to specialized cell compartments that break down (degrade) or recycle them. This process helps to maintain the proper balance of protein production and breakdown (protein homeostasis) that cells need to function and survive. Studies suggest that STAM binding protein is also involved in multiple chemical signaling pathways within cells, including pathways needed for overall growth and the formation of new blood vessels (angiogenesis).  Mutations in the STAMBP gene reduce or eliminate the production of STAM binding protein. This shortage allows damaged or unneeded proteins to build up inside cells instead of being degraded or recycled, which may damage cells and cause them to self-destruct (undergo apoptosis). Researchers suspect that abnormal apoptosis of brain cells starting before birth may cause microcephaly and the underlying brain abnormalities found in people with microcephaly-capillary malformation syndrome. A lack of STAM binding protein also alters multiple signaling pathways that are necessary for normal development, which may underlie the capillary malformations and other signs and symptoms of the condition.