In our study, 105 patients with CAD, age ≤ 35 years, and LDL-C ≥ 3.4 mmol/L were evaluated for 9 genes (LDLR, APOB, PCSK9, APOE, STAP1, LIPA, LDLRAP1, ABCG5/8) for FH diagnosis. The gene discussed is LDLRAP1; the disease is coronary artery disorder.