PAH and phenylketonuria: Here, our LNP-formulated mouse Pah mRNA proofed to be therapeutically active at lower doses (1.63–1.82 mg/kg in comparison to 3–10 mg/kg in the Perez-Garcia et al., 2022 study) in lowering Phe in PKU mouse serum after each of the five injections, and most importantly to reduce Phe in brain, the most affected organ in PKU patients.