The fine-mapping association study of UBAC2 identified six risk SNPs for BD in the Chinese cohort; three of them were verified in validation study (rs3825427, first-stage Pc = 2.2 × 10-3, second-stage Pc = 9.3 × 10-3, combined Pc = 6.9 × 10-6; rs9517668, first-stage Pc = 1.7 × 10-3, second-stage Pc = 0.03, combined Pc = 3.3 × 10-4; rs9517701, first-stage Pc = 5.1 × 10-3, second-stage Pc = 9.0 × 10-3, combined Pc = 2.9 × 10-5; respectively).