An Adolescent Substance Prevention Model Blocks the Effect of CHRNA5 Genotype on Smoking During High School.
BACKGROUND
Prevention intervention programs reduce substance use, including smoking, but not all individuals respond. We tested whether response to a substance use prevention/intervention program varies based upon a set of five markers (rs16969968, rs1948, rs578776, rs588765, and rs684513) within the cluster of nicotinic acetylcholine receptor subunit genes (CHRNA5/A3/B4).


METHODS
Participants (N = 424) were randomly assigned to either control condition, or a family-based intervention in grade 6 and a school-based drug preventive intervention in grade 7. Smoking in the past month was assessed in grades 9-12 using a four-point scale (0 = never smoked, 1 = smoked but not in last month, 2 = one or a few times, 3 = about once a week or more).


RESULTS
There was a main effect of both the intervention (b = -0.24, P < .05) and genotype at rs16969968 (b = 0.14, P < .05) on high school smoking. Using dummy coding to allow for nonlinear effects, individuals with the A/A genotype smoked more often than those with G/G (b = 0.33, P < .05). A genotype × intervention effect was found with reduced smoking among those with A/A and G/A genotypes to levels similar to those with the G/G genotype (G/G vs. A/A: b = -0.67, P < .05; A/G vs. A/A: b = -0.61, P < .05; G/G vs. A/G ns). Results were nonsignificant for the other four markers.


CONCLUSIONS
Preventive interventions can reduce the genetic risk for smoking from rs16969968.
Department of Biobehavioral Health, Penn State University, University Park, PA; Institute for the Neurosciences, Penn State University, University Park, PA; Molecular Cellular and Integrative Biosciences Program, Penn State University, University Park, PA; djv4@psu.edu.
David J
DJ
Vandenbergh
Department of Biobehavioral Health, Penn State University, University Park, PA; Department of Human Development and Family Studies, Penn State University, University Park, PA;
Gabriel L
GL
Schlomer
Department of Human Development and Family Studies, Penn State University, University Park, PA;
H Harrington
HH
Cleveland
Molecular Cellular and Integrative Biosciences Program, Penn State University, University Park, PA;
Alisa E
AE
Schink
Department of Biobehavioral Health, Penn State University, University Park, PA; Department of Human Development and Family Studies, Penn State University, University Park, PA;
Kerry L
KL
Hair
Bennett Pierce Prevention Research Center, Penn State University, University Park, PA;
Mark E
ME
Feinberg
Department of Psychology, Penn State University, University Park, PA;
Jenae M
JM
Neiderhiser
Department of Human Development and Family Studies, Penn State University, University Park, PA; Bennett Pierce Prevention Research Center, Penn State University, University Park, PA;
Mark T
MT
Greenberg
Partnerships in Prevention Science Institute, Iowa State University, Ames, IA.
Richard L
RL
Spoth
Partnerships in Prevention Science Institute, Iowa State University, Ames, IA.
Cleve
C
Redmond
D000293:Adolescent; D000294:Adolescent Behavior / Q000502:physiology*; D005260:Female; D005838:Genotype; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D009419:Nerve Tissue Proteins / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide / Q000235:genetics; D011978:Receptors, Nicotinic / Q000235:genetics*; D012307:Risk Factors; D012574:Schools; D012907:Smoking / Q000453:epidemiology / Q000235:genetics*; D000074606:Smoking Prevention; D013334:Students
C447158:CHRNA5 protein, human; D009419:Nerve Tissue Proteins; D011978:Receptors, Nicotinic