CLCN5 and focal segmental glomerulosclerosis: Similarly confusing is the finding that several genetic abnormalities that cause tubular disorders [32] have been reported to cause FSGS, such as CLCN5, mutated in Dent disease 1 [33], and SLC12A1, mutated in Bartter syndrome type 1 [34], although these are not always included in lists of genetic causes of FSGS.