This SNP is located in an alternatively spliced exon of the OPRM1 gene and is found only in the MOR1X isoform. Preliminary data suggest that when expressed in cultured cells, this isoform differs significantly from the typical MOR1 isoform in its regulation by membrane trafficking (M. Tanowitz, M. von Zastrow, personal oral communication, 2008).
[PMID 15558714] Novel exonic mu-opioid receptor gene (OPRM1) polymorphisms not associated with opioid dependence.
[PMID 19053977] OPRM1 Asn40Asp predicts response to naltrexone treatment: a haplotype-based approach.
[PMID 19103668] Expansion of the human mu-opioid receptor gene architecture: novel functional variants.
[PMID 20194481] Association of mu-opioid receptor variants and response to citalopram treatment in major depressive disorder.
[PMID 23144877] A Non-Synonymous Single Nucleotide Polymorphism in an OPRM1 Splice Variant Is Associated with Fentanyl-Induced Emesis in Women Undergoing Minor Gynaecological Surgery