In the above-mentioned study by Zhang et al., haptoglobin was found to be increased using an ELISA in 19 patients with GBS (GBS: 2.54 ± 0.46 mg/dL, OND: 0.48 ± 0.07 mg/dL, p < 0.001). The gene discussed is HP; the disease is Guillain-Barre syndrome.