Molecular characteristics

The SLC25A22 gene encodes a protein that is expressed in mitochondria, a key cellular component that produce the energy of the cell. This protein transport intracellular glutamate into mitochondria and is named GC1 (glutamate carrier 1). GC1 is highly expressed in brain, liver and pancreas.
The SLC25A22-related disorder is caused only if both parents have one pathogenic variant (same or different) and transmit it to their child. This kind of transmission is called autosomal recessive. To date, 12 pathogenic variants have been described in 21 patients from 12 different families. These variants result in a total loss of function of the protein meaning that the mutated GC1 could not transport anymore glutamate into the mitochondria. This could perturb glutamate concentration in the brain. This concentration should be tightly controlled since glutamate is one of the major molecules that conduct messages from one nerve cell to another.