SLC6A3 and delirium: A further meta-analysis concluded that the homozygous AA genotype of rs393795 in the SLC6A3 gene was more frequent in patients without delirium, and the homozygous GG genotype of rs6276 in the DRD2 gene was more frequent in patients without delirium after adjustment for cognitive impairment (van Munster et al., 2010b).