A functional prodynorphin promoter polymorphism and opioid dependence.
OBJECTIVE
The prodynorphin gene (PDYN) promoter has a repeat polymorphism that is functionally important in association with substance abuse. We examined this polymorphism for association in our sample of 168 opioid-dependent patients and 122 ethnically and geographically matched controls.


METHODS
Patients were selected from university-affiliated residential and non-residential addiction treatment programs in the Philadelphia area. A sample of blood was drawn from consenting individuals and genomic DNA was isolated. Polymerase chain reaction amplification of the PDYN promoter was performed and various genotypes were determined on the basis of differing sizes of the polymerase chain reaction products. The genotype and allele data were analyzed by Fisher's exact test.


RESULTS
A significant difference in genotype (P<0.0006) and allele (P<10) frequencies was found between the African American and European American populations. We did not detect any significant difference in genotype or allele frequencies between the patients and controls within the European American ethnic group. However, we detected a weak association (P=0.013) when we compared allele frequencies of patients and controls in the African American population.


CONCLUSIONS
These data suggest that the PDYN repeat polymorphism should be studied in additional opioid-dependent populations.
Ray
Riju
R
Department of Pharmacology, University of Pennsylvania, Philadelphia, 19104, USA. rijuray@mail.med.upenn.edu
Doyle
Glenn A
GA
Crowley
James J
JJ
Buono
Russell J
RJ
Oslin
David W
DW
Patkar
Ashwin A
AA
Mannelli
Paolo
P
DeMaria
Peter A
PA
O'Brien
Charles P
CP
Berrettini
Wade H
WH
D004745:Enkephalins / Q000235:genetics*; D005006:Ethnicity / Q000235:genetics; D005838:Genotype; D006801:Humans; D009293:Opioid-Related Disorders / Q000235:genetics*; D015143:Philadelphia; D011110:Polymorphism, Genetic; D011401:Promoter Regions, Genetic; D011498:Protein Precursors / Q000235:genetics*; D012091:Repetitive Sequences, Nucleic Acid
D004745:Enkephalins; D011498:Protein Precursors; C033660:preproenkephalin