SCNN1A and pseudohypoaldosteronism, type IB1, autosomal recessive: The second type of PHA-1 is the generalized, systemic PHA-1 form, also called autosomal recessive PHA-1 (or PHA-1B), caused by loss-of-function mutations in the SCNN1A, SCNN1B, and SCNN1G, genes which encode α-, β- and γ-ENaC subunits, respectively [135].