SLC6A3 and Borderline personality disorder: The odds of BPD in patients in highest risk categories were those with the G,G variant of HTR1A and either 9,9 (OR, 5.42) or 9,10 (OR 6.64) genotypes of DAT1. Moreover, the odds of BPD in patients with the highest risk category (9,10; G,G) were about nine times greater than those in the lowest risk category (10,10; C,G).