Such investigations however, raise an important issue regarding the specificity of endophenotypes for alcoholism, given that a series of common genes may be associated with a host of psychopathological behaviors. It is possible that common factors may confer risk for several psychopathologies. For instance, personality factors, such as impulsivity and sensation/novelty-seeking, may also represent a common index of vulnerability to various psychopathologies. The hypothesis that common factors may confer risk or protection to more than one form of psychopathology led investigators to refine the endophenotypes such that they become better defined and possibly more psychopathology-specific. However, one should not cling thoughtlessly to current mental disease classifications when data regarding endophenotypes may be suggesting new relationships between causal factors and disease manifestations.
