Polymorphisms in the glutamate decarboxylase 1 gene associated with heroin dependence

► There is a finding of rs1978340 allele frequencies with heroin dependence. ► There is a finding of rs3791878 allele frequencies with heroin dependence. ► There is a finding of rs11542313 allele frequencies with heroin dependence. ► Significantly more C-C-C-C-A haplotypes were found in case subjects. ► Significantly fewer T-C-A-C-A haplotypes were found in case subjects.