The rs10497520 (TTN) T allele was associated with decreased risk in patients with a family history of BC or early-onset BC (OR = 0.6, p < 0.0001 and OR = 0.7, p = 0.05, respectively), and rs2242442-G (TBX3) also demonstrated a protective effect (OR = 0.6, p = 0.02). Here, TBX3 is linked to breast cancer.