Variants showing weak FH bands under nonreducing SDS-PAGE. Coomassie-stained gels showing each FH variant compared with equal amounts of wild-type (WT) FH protein (measured as optical density at absorbance at 280 nm). Asterisks indicate FH variants that were previously described to be associated with no-expression alleles or decreased FH plasma levels (see supplemental Table 3). Differences in expression levels were confirmed in all cases by enzyme-linked immunosorbent assay measurements.