Borderline personality disorder (BPD) is characterized by pervasive instability in moods, interpersonal relationships, self-image and behaviour and can lead to suicidal behaviour, substance abuse and failed relationships. It is more common than schizophrenia or bipolar disorder and is estimated to affect 2% of the population. A Dutch study of 711 pairs of twins and 561 parents looked into the genetic influences on BPD and found evidence for a link with chromosome 9. Another study by the same group of researchers looked at 5,496 twins in the Netherlands, Belgium and Australia and found that 42% of variation in BPD features was due to genetic factors and 58% due to environmental ones. There were no significant differences in the extent to which men and women inherited BPD and young adults displayed more BPD features than older ones.
You can find out more about this research by going to