A large inter-individual variability in the dose–response relationship in ionizing radiation-induced focus counts per nucleus in patients with differentiated thyroid carcinoma was reported by Lassmann et al. [25] and by Eberlein et al. [26], by using γ-H2AX and sensor p53-binding protein 1 (53BP1) to the DSB-containing chromatin. The gene discussed is TP53BP1; the disease is thyroid gland carcinoma.