Considering the capacity of LAT1 to control the transport of Phe and subsequently alter the clinical outcome of PKU, several studies have aimed to identify functional genetic variants in SLC7A5. As of now, only a few rare missense variants have been found in the coding regions of this gene, and they do not have a clear potential to impact LAT1 function22,23. The gene discussed is SLC7A5; the disease is phenylketonuria.