Table 1.
Complement Profile
| Pedigree No. |
Reference Range | |||||
|---|---|---|---|---|---|---|
| I-2 | II-1 | II-2 | II-4 | II-3a | ||
| CFHR5 sequence variant | Yesb | Yesb | No | No | Yesb | |
| C3 (g/L) | 1.43 | 1.03 | 1.08 | 1.14 | 0.07 | 0.7-1.7 |
| C4 (g/L) | 0.24 | 0.17 | 0.21 | 0.16 | 0.22 | 0.16-0.54 |
| CFH (%)c | 181 | 132 | 132 | 147 | 148 | |
| CFI (%)c | 174 | 132 | 157 | 186 | 154 | |
| Total complement hemolytic activity (%)d | 108 | 47 | 99 | 95 | ND | 50-150 |
| Alternative pathway hemolytic activity (%)d | 92 | 53 | 102 | 95 | ND | 50-150 |
| Serum CFHR5 | ||||||
| Absolute amount (μg/mL) | 5.3 | 3.8 | 4.0 | NA | 2.1 | 3.4-10.1 |
| Relative amount (%)e | 96.2 | 69.9 | 72.5 | NA | 37.3 | |
Abbreviations: CFH, complement factor H; CFHR5, complement factor H-related protein 5; CFI, complement factor I; NA, not available (insufficient sample); ND, not detectable.
Index patient.
c.485dupA (p.Glu163Argfs*34); numbering and nomenclature follows Human Genome Variation Society recommendations (for cDNA, A in ATG start codon is position 1; for protein, the methionine encoded by the start codon is position 1).
No validated reference range exists for CFH and CFI, so results are expressed as percentage of the level in pooled serum from apparently healthy controls.
Percentage of the activity in pooled serum from apparently healthy controls.
Compared with the median value in 13 apparently healthy controls, which was 5.5 μg/mL (Fig 1D).