Association of substance use disorders with childhood trauma but not African genetic heritage in an African American cohort.
OBJECTIVE
Genetic variation influences differential vulnerability to addiction within populations. However, it remains unclear whether differences in frequencies of vulnerability alleles contribute to disparities between populations and to what extent ancestry correlates with differential exposure to environmental risk factors, including poverty and trauma.


METHODS
The authors used 186 ancestry-informative markers to measure African ancestry in 407 addicts and 457 comparison subjects self-identified as African Americans. The reference group was 1,051 individuals from the Human Genome Diversity Cell Line Panel, which includes 51 diverse populations representing most worldwide genetic diversity.


RESULTS
African Americans varied in degrees of African, European, Middle Eastern, and Central Asian genetic heritage. The overall level of African ancestry was actually smaller among cocaine, opiate, and alcohol addicts (proportion=0.76-0.78) than nonaddicted African American comparison subjects (proportion=0.81). African ancestry was associated with living in impoverished neighborhoods, a factor previously associated with risk. There was no association between African ancestry and exposure to childhood abuse or neglect, a factor that strongly predicted all types of addictions.


CONCLUSIONS
These results suggest that African genetic heritage does not increase the likelihood of genetic risk for addictions. They highlight the complex interrelation between genetic ancestry and social, economic, and environmental conditions and the strong relation of those factors to addiction. Studies of epidemiological samples characterized for genetic ancestry and social, psychological, demographic, economic, cultural, and historical factors are needed to better disentangle the effects of genetic and environmental factors underlying interpopulation differences in vulnerability to addiction and other health disparities.
Ducci
Francesca
F
Division of Psychological Medicine, PO63, Institute of Psychiatry, De Crespigny Park, London SE5 8AF, UK. francesca.ducci@kcl.ac.uk
Roy
Alec
A
Shen
Pei-Hong
PH
Yuan
Qiaoping
Q
Yuan
Nicole P
NP
Hodgkinson
Colin A
CA
Goldman
Lynn R
LR
Goldman
David
D
D001741:Black or African American / Q000235:genetics*; D044383:Black People / Q000235:genetics; D002648:Child; D002649:Child Abuse / Q000523:psychology / Q000706:statistics & numerical data*; D005260:Female; D005819:Genetic Markers; D020022:Genetic Predisposition to Disease / Q000235:genetics; D014644:Genetic Variation / Q000235:genetics; D005828:Genetics, Population; D005838:Genotype; D054625:Healthcare Disparities / Q000706:statistics & numerical data; D006801:Humans; D008016:Life Change Events; D008297:Male; D008875:Middle Aged; D008957:Models, Genetic; D010641:Phenotype; D020641:Polymorphism, Single Nucleotide; D012307:Risk Factors; D012959:Socioeconomic Factors; D019966:Substance-Related Disorders / Q000453:epidemiology / Q000235:genetics*
D005819:Genetic Markers