LDLR and familial hyperaldosteronism: Mutations in LDLR gene range from defective (characterized by a residual receptor function) to null (with no functional receptor protein), and the severity of FH is also related to the presence of the genetic defect in only one allele (heterozygous FH, HeFH) or in both (homozygous FH, HoFH), with the latter having the lowest prevalence but the most severe phenotype.