> To induce alcohol dependence, we used the two bottle choice - chronic intermittent ethanol vapor exposure (2BC-CIE) paradigm, as previously described (Patel et al. 2019). This method consistently produces alcohol dependence in C57BL/6J mice (Becker and Lopez 2004; Bajo et al. 2016; Huitron-Resendiz et al. 2018), as exhibited by escalated alcohol intake, anxiety-like behavior and reward deficits. Briefly, mice were exposed to limited access alcohol (15% w/v) and water - two bottle choice (2BC) sessions followed by either chronic intermittent alcohol (CIE) exposure in vapor chambers (La Jolla Alcohol Research, La Jolla, CA), to induce alcohol dependence (dependent mice) or control air exposure (non-dependent control mice) in identical chambers. Naïve mice were not exposed to any alcohol either by drinking or vapor exposure.

A diagram on a similar study can be found at https://www.researchgate.net/figure/A-General-CIE-protocol-f... - for the diagram from this study, see page 4.

this says 10% of the people drink 60% of the alcohol