The highest S100β level was similarly associated with the infarct volume in patients with stroke in either hemisphere (dominant: β 36.853, 95% confidence interval (CI) 22.659–51.048, P < 0.001; non-dominant: β 23.645, 95% CI 10.774–36.516, P = 0.007). The gene discussed is S100B; the disease is stroke disorder.