mu opioid receptor gene: new point mutations in opioid addicts

introduction: association between single-nucleotide polymorphisms (snps) in mu opioid receptor gene and drug addiction has been shown in various studies. here, we have evaluated the existence of polymorphisms in exon 3 of this gene in iranian population and investigated the possible association between these mutations and opioid addiction.  methods: 79 opioid-dependent subjects (55 males, 24 females) and 134 non-addict or control individuals (74 males, 60 females) participated in the study. genomic dna was extracted from volunteers’ peripheral blood and exon 3 of the mu opioid receptor gene was amplified by polymerase chain reaction (pcr) whose products were then sequenced.  results: three different heterozygote polymorphisms were observed in 3 male individuals: 759t>c and 877g>a mutations were found in 2 control volunteers and 1043g>c substitution was observed in an opioid-addicted subject. association between genotype and opioid addiction for each mutation was not statistically significant.  discussion: it seems that the sample size used in our study is not enough to confirm or reject any association between 759t>c, 877g>a and 1043g>c substitutions in exon 3 of the mu opioid receptor gene and opioid addiction susceptibility in iranian population.