For years, its been a controversial side effect of antidepressants: for all the patients helped by the drugs, there was a smaller cohort for whom the beginning of treatment triggers a descent into thoughts of suicide. Actual suicides are rare, but suicidal ideation can emerge in as many as one in twelve patients, most commonly in their first months on the drugs. Doctors can monitor for the side effects, but its been a persistent danger, even as antidepressant use has skyrocketed. Scientists at the Max Planck Institute isolated 79 genetic markers correlated with an increased risk of antidepressant-induced suicidality.