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Subject Area:Further Areas
Journal: Cellular Physiology and Biochemistry
Cellular Physiology and Biochemistry (1993) 3 (3-4): 231–244.
Published Online: 04 September 2008
... appear to represent the ancestral opioid gene. This review will consider the following hypothesis: the evolution of the opioids occurred as a result of two duplications of the proenkephalin gene. In this hypothesis, the first duplication event would have given rise to the proopiomelanocortin gene...