All relatives of FD patients that participated in this study as matched controls were known to carry one copy of the ELP1 founder mutation (previously screened at the Dysautonomia Center, NYU Langone Health) and even though carriers are asymptomatic with respect to typical FD symptoms3, there is a possibility that the founder allele is penetrant at the level of microbiome diversity. The gene discussed is ELP1; the disease is Fabry disease.