Microbiome Outcomes in PKU Patients on Palynziq with Normal Diets Compared to PKU Patients Using Traditional Therapies

PKU patients who have been treated with Palynziq (previously BioMarin investigational drug PegValiase) present a unique population to distinguish microbiome changes based on disease only as these patients are now eating a “normal” diet and have low blood phenylalanine levels. By comparing these patients to other classic PKU patients on traditional low protein diets with low blood phenylalanine levels we can see if normalizing the diet in fact does normalize the gut microbiome or if the disease itself contributes to the altered microbiome. We hypothesize that the microbiome of patients treated with Playnzig will look more closely related to a traditional microbiome than the patients eating a low protein diet. We will test this hypothesis with the following specific aims: 1. Compare the microbiome of classic PKU patients on a normal protein diet (eating >RDA for protein from intact sources and no metabolic formula for >1year) with phe levels