Thirdly, the socio-demographic characteristic of the samples is extremely dis-homogeneous in terms of gender, race, ethnicity, etc. In this regard, few studies specifically investigated (if any) differences occur in the association between CRP levels and depression, considering gender, ethnicity, type of MDD severity, clinical course, illness duration, type of concomitant treatment and so forth. The gene discussed is CRP; the disease is depressive symptom measurement.