Despite a great deal of interest in the cluster of GABAA genes located in chromosome 4, the functional significance of this (rs1497570), or any other, polymorphism of the GABRG1 gene remains unknown. As stated by Enoch et al. (2009), the extensive pattern of LD in the 4-gene cluster located in chromosome 4 suggests the presence of distant enhancers and suppressors; however, basic molecular genetics research is needed to identify a functional locus, or loci, in this gene cluster. As is the case for genetic associations to polymorphisms of unknown functional significance, LD to a functional variant represents an important and plausible, alternative explanation, whereby the signal detected in this study at the rs1497571 locus may be a result of its close proximity to a functional polymorphism.
