As shown in Table 3, at multivariate analysis, anaemia was associated with being underweight (odds ratio (OR) 2.93, 95% CI 1.70–5.05, P < 0.01), low CD4:CD8 ratio (OR 2.54, 95% CI 1.07–6.04, P = 0.035) and hypochromia (OR 4.23, 95% CI 2.17–8.25, P < 0.01). The gene discussed is CD4; the disease is anemia.