A common gene variant was associated with a nearly doubled likelihood of posttraumatic stress disorder (PTSD) in at-risk urban women -- but not in otherwise similar men, researchers said.
The affected gene encodes a receptor protein believed to mediate stress responses, and is also modulated by estrogen signaling, according to Kerry Ressler, MD, PhD, of Emory University in Atlanta, reporting in the Feb. 24 issue of Nature.
Heavily traumatized civilian women with two copies of a specific single nucleotide polymorphism (SNP) in the ADCYAP1R1 gene were more likely to show PTSD with an odds ratio of 1.66 (95% CI 1.32 to 2.09) relative to similar women without the condition, Kessler and colleagues found.
The same SNP -- called rs2267735, substituting a cytosine base for a guanine -- in men exposed to fearful situations showed no association with PTSD, the researchers also found (OR 0.95, 95% CI 0.71 to 1.27).
The authors did point out, however, that women are more likely to develop PTSD than men, and this discrepancy may relate to the modulation of the receptor pathway by estrogen....