The question of whether the genetic associations between PTSD and alcohol consumption differs compared to alcohol-related problems phenotypes has not been explicitly studied, to our knowledge. However, work on other psychiatric phenotypes suggests that for some, like smoking behaviors, the genetic correlations between mild and more problematic versions of the phenotype [e.g. cigarettes per day (CPD), nicotine dependence (ND)] are strongly positively correlated with each other (rG = 0.95; Quach et al., 2020). Additionally, their correlations with other disorders (e.g. schizophrenia) are in the same direction (e.g. both positive) but of varying sizes (Hartz et al., 2018). Research on major depression, which is closely related to PTSD, found positive genetic correlations between major depression and AD and alcohol quantity, but negative genetic correlations between major depression and alcohol frequency (Polimanti et al., 2019). Thus, we aim to test whether using alcohol consumption -related phenotypes yields similar estimates to problem alcohol-related phenotypes.
