Table 1.
Enzyme properties of SRD5A2 missense substitutions.
| Substitution | Testosterone Km (mM) | NADPH Km (mM) | Vmax (nmol/min/mg) |
|---|---|---|---|
| WT (normal range) | 0.9 (0.7–1.0) | 8 (6–14) | 1.9 (1.7–2.2) |
| Single-point variant | |||
| P30L (rs61748121) | 2.1 | 21 | 0.5 |
| P48R (rs61748122) | 2.2 | 12 | 1.2 |
| A49T (rs9282858) | 2.7 | 7 | 9.9 |
| V89L (rs523349) | 0.6 | 8 | 1.1 |
| T187M (rs61748125) | 1.1 | 47 | 0.8 |
| F194L (rs61748126) | 0.7 | 19 | 2.2 |
| R227Q (rs9332964) | 4.6 | 38 | 0.06 |
| F234L (rs9332966) | 1.6 | 21 | 1.4 |
| Compound heterozygote | |||
| V89L–A49T | 1.2 | 8 | 5.5 |
| Haplotype (i.e., double mutant) | |||
| V89L–A49T | 0.8 | 8 | 2.9 |
Km: Michaelis constant; NADPH: Nicotinamide adenine dinucleotide phosphate; Vmax: Maximum rate of reaction; WT: Wild-type.
Reproduced with permission from [23].