recent study failed to observe the same effect (Oslin et al., 2015; Sloan et al., 2018), but reported that G-allele carriers consume more drinks per day, on average. This study’s findings may differ from previous meta-analyses because the authors omitted studies that were not randomized clinical trials, which could explain the discrepancies between studies. This could be explained by multiple genetic components, for example, the selection of specific ethnic backgrounds included in the study, since the minor allele frequency of rs1799971 is variable among different ethnic groups, and potentially confounded by the presence or absence of other linked genetic variants. To control for this possibility, we have modeled contrasting rs1799971 genotypes in a CRISPR-edited, isogenic set of human-induced pluripotent (iPS) cells (Halikere et al., 2019).
