SLC1A4 deficiency is associated with microcephaly (small head size) and developmental delays. The condition is genetic. We do not yet fully understand why mutations in SLC1A4 cause neurological problems, but we know that it has something to do with amino acid movement into the brain cells. SLC1A4 allows certain amino acids to get into the brain cells, and defects in SLC1A4 prevent these essential molecules from getting into the brain cells to do their job and make the brain work. We invite families with SLC1A4 deficiency to help us figure this out by contacting us. We need to better understand why SLC1A4 deficiency causes problems with brain function so we can develop new treatments. New treatments could involve trying to find other ways to get those amino acids into the brain cells.
SLC1A4 deficiency is a genetic condition that occurs when a change or mutation in DNA is inherited from both parents in an autosomal recessive manner, which means that both copies of the SLC1A4 gene in each cell have the mutation. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but do not show signs and symptoms of the condition. The most common mutation we have seen is the Glu256Lys mutation, which we have seen in Jewish families. This means that at the 256th amino acid of the SLC1A4 gene, there is a Glutamic acid instead of a Lysine. Although we do not yet know this for sure, we believe the condition is likely to be more common in individuals of Jewish ancestry. We know that 1 in 144 (0.7%) individuals of Ashkenazi Jewish ancestry carry the Glu256Lys mutation. If both parents carry a SLC1A4 mutation, there is a 25% chance of having a child with SLC1A4 deficiency every time they have a child.
What we know:
From our work so far, SLC1A4 deficiency appears to be an isolated neurological condition, with no other health problems. SLC1A4 deficiency does not appear to be associated with neurodegeneration. (For more information, please look at our publication on a group of families with this condition and the scientific background.)
What we don’t know:
While we’re learning more with every new family, there is still a lot left to learn. If you are a parent or family member of someone with SLC1A4 deficiency, or if you are a clinician or researcher working with a patient with this condition, we would love to learn from you. We believe that families, clinicians, and researchers all working together and sharing our experiences, will benefit everyone.
What we’re doing:
We are working on studies to try to better understand and hopefully someday treat people with this condition. We are working to understand what the gene change does to the developing brain and how it affects behavior and brain function. Ultimately, we will test potential treatments in cellular and animal models of the condition.