Of the 21 molar ratios that may reflect 5β-reductase (AKR1D1) functioning, 2 are lower, 16 are not significantly different, and 3 are higher in patients compared to controls (p = 0.672, Mann–Whitney test), suggesting the absence of a significant trend in relation to schizophrenia, as in the case of 5α-reductases. The gene discussed is AKR1D1; the disease is schizophrenia.