The burden of comorbid illness (beyond AUDs) is known to be higher in clinical samples (Kaufmann et al., 2014) and they differ on a number of demographic and disease-related characteristics (Blanco et al., 2015). It is also plausible that the mechanisms underlying alcohol problems in treatment-seeking individuals differ from those driving alcohol problems in the general population, particularly when clinical samples are obtained based on family history of AUD, which can represent both different genetic predispositions and contextual risk factors associated with the familial environment. Proposed typologies of alcoholism (e.g. Cloninger et al., 1988) also suggest that individuals with a prominent family history of AUDs have a more strongly genetically influenced form of the disorder, although it is not known whether the genetic influences may also differ qualitatively from those involved in sporadic onset cases.
