Marlene,

There are studies here in the information sections and within world news surrounding these exact issues; what ultimately causes one to get PTSD opposed to another! They don't know, and there is no scientific proof to the actual vunerability as yet. They don't even know if it is actually a vunerability at all, but simply more the realistic nature of the issue itself, being how the individual perceives an incident as traumatic to themselves.

Veiled has a twin, suffered the same abuse, she got PTSD her twin sister didn't. Same genetics, same abuse, same instances, one has, one hasn't. Why? Because even though they are twins, both still have their own unique personalities, which veiled perceived the trauma worst than her sister, hence PTSD. Veiled could have also suffered more, in that she didn't actually have PTSD until another calalyst trauma affected her uniquely, instead could have only had symptoms based on PTSD earlier. Who knows? Nobody at this stage in life.

Doctors are looking for genetic flaws, similarities, brain scans, etc etc etc; and just when they think they find similiarities, someone pops up without that similiarity at all, same outcome, thus back to the drawing board. They cannot find a common similarity genetically pre-PTSD, only post PTSD with parts of the brain reducing in size and so forth.

They have studied groups of soldiers pre-deployment, then post deployment, PTSD presents, still nothing in common apart from the exposure to trauma and that each individual felt helpless or fearful about the incident individually.

I understand what your searching for Marlene, but the doctors themselves can't find as yet either with all their studies. What they do manage to find, is what they go out looking for, ie. take specific cases of PTSD only, look for specific traits, etc, to find the answer they often want, which is an incorrect methology for a study, but hey; you can't tell them, because their the doctors, and they know it all apparently.