Copper is an essential trace element for all living cells which therefore have a special transporter called CTR1. In humans, this CTR1 copper transporter is coded for by the gene SLC31A1. If both the gene copies inherited from the mother and the father are flawed by a mutation, the cells cannot take up copper properly. While this creates problem for many types of cells, nerve cells in the brain are the most severely affected ones.
SLC31A1