Table 3 shows a comparison of genotype frequencies between case-control groups. When genotype distributions between the SLE (control) and SLE_ONFH (case) groups were compared, the SNPs rs3813946 in 5′-UTR (untranslated region), rs311306 in intron 1, and rs17615 in exon 10 (nonsynonymous SNP; G/A, Ser639Asn) of the CR2 gene, located in block 1, demonstrated the evidence for association with risk of ONFH under recessive model (P values; 0.004~0.016). None of block 2 SNPs showed evidence for association (Table 3). The gene discussed is CR2; the disease is systemic lupus erythematosus.