One study found that a family member of someone with BPD is almost four times more likely to develop BPD than a nonrelative.4 Another study of twins examining all nine BPD criteria also concluded that most genetic effects on BPD criteria derive from one heritable general BPD factor. In this research, impulsivity levels in BPD patients appeared to be more highly heritable. In contrast, interpersonal and self-image features were less connected among family members, suggesting these symptoms were more likely influenced by life experiences and were less genetically determined.5 Some
