of diseases (Orozco et al., 2010). The most likely solution to this problem would be the incorporation of both common and rare genetic variants in genetic studies of alcohol using whole genome sequencing platforms. Unfortunately, a noteworthy drawback to the inclusion of rare-moderately-penetrant and common-weakly-penetrant alleles in the genetic model of any disease is that it decreases the power to detect true associations. As a result, larger studies of AD would be necessary (Wray et al., 2007, 2008); alternatively, family-based association studies, such as the Collaborative Studies on the Genetics of Alcoholism, would continue to have great utility as they are better powered to detect rare variants. Capitalizing on the idea that common variants can capture variance attributable to low-frequency functional variants, whole genome prediction models (WGPMs), such as genome-wide complex trait analysis (Yang et al., 2011b), have been able to capture more of the variability in complex traits (e.g., height and body mass index) using current genotyping platforms (Lee et al., 2011), thus demonstrating that cumulative/aggregate genetic risk scores should prove useful in capturing more of the missing heritability (De Jager et al., 2009; Kohli et al., 2010; Purcell et al., 2009). However, a notable limitation of these models
