Analysis of neuropeptide Y (NPY) gene in cannabis users

Substance addiction is a kind of complex and multifactorial disease that develops basedon environmental and genetic factors. Cannabis that is the most frequently used illegalsubstance. Neuropeptide Y (NPY), which is subject to our research interest, is aneurotransmitter, consists of 36 amino acid and regulates many physiologic events.The role of T1128C polymorphism that causes amino acid change at NPY gene at thecannabis users and healthy individuals in Turkey and determining genotype distributionand allele frequency have been aimed in this research. At the planned studies obtainedfrom peripheral blood, NPY gene T1128C polymorphism of DNAs were analyzed in139 cannabis users and 100 healthy individuals by using polymerase chain reaction andrestriction fragment length polymorphism (PCR-RFLP) procedures. Genotypedistribution and allele frequency of T1128C polymorphism were found as 95%, 5 % and0%; T=0.975, C=0.025 at the cannabis users group and 95%, 5 % and 0%; T=0.975,C=0.025 at the control group respectively. It has been determined that there is nostatically significant difference between the cannabis users than healthy control group(p>0.05). It has been also found that there is no difference between expected andobserved genotype distribution and allele frequency according to Hardy-WeinbergEquilibrium (HWE) (HWE cannabis addict p=760, HWE control p=0.797). When theallele frequency of healthy people is compared with other populations; it has beendetermined that it is coherent with European American, African American, China,Germany, Brazil, Sweden and Finland (p>0.05). On the contrary, the results obtainedwere of different than the Japanese population (p=0.022).In conclusion, NPY gene T1128C polymorphism did not reveal any relationship withthe cannabis addiction. It may, there fore, be useful for considering to study NPY genereceptors and/or other related genes for elucidating the genomic basis of addiction.Key Words: Cannabis addiction, Neuropeptide Y, T1128C polymorphism