While a number of phenotypic factors can affect the risk for alcoholism, one of the most studied endophenotypes is an individual’s level of response to alcohol during their early experience with alcohol (Heath et al., 1999). The level of response to alcohol can be reliably measured with the Subjective High Assessment Scale (SHAS) during an alcohol challenge or by the Self-Rating of the Effects of Alcohol (SRE) which uses recall to establish the number of drinks required to reach an effect. Children of alcoholics have a greater risk for alcoholism when they have a lower level of response (Pollock, 1992; Schuckit et al., 2000; Schuckit and Smith, 1996). A low level of response established early in an individual’s drinking career can lead to higher future drinking levels (Ehlers et al., 1999; Heath et al., 1999; Volavka et al., 1996). Populations at historically higher risk for alcoholism, such as Native American or Korean, need to consume larger amounts of alcohol to become intoxicated (Garcia-Andrade et al., 1997; Luczak et al., 2002; Wall et al., 1999) compared to those with lower risk
