Study Report

Study Information

Basic Info
Reference |
Humphreys, K. L.,2014 PMID: 25329975
|
Citation |
Humphreys, K. L., et al. (2014). "Race moderates the association of Catechol-O-methyltransferase genotype and posttraumatic stress disorder in preschool children." J Child Adolesc Psychopharmacol 24(8): 454-457. |
Phenotype |
Total PTSD symptoms, PTSD diagnosis, PTSD category B symptom, PTSD category C symptom, PTSD category D symptom |
Trauma |
Various |
Study Design |
Case-control |
Study Type |
Candidate gene association study, Gene-environment interaction study |
Sample Size |
171 children (152 African American and European American) |
SNP/Marker Size |
1 SNP |
Predominant Ethnicity |
Caucasian, Black |
Population |
Black, White, mixed, and other. |
Gender |
met/met: 8 male and 4 female; val/met: 61 male and 37 female; val/val: 37 male and 24 female. |
Age |
3-6 years old |

Detail Info
Sample Diagnosis |
Not mentioned |
Related Diagnostic Tools |
Preschool Age Psychiatric Assessment |
Sample Status |
PTSD diagnosis and symptom counts were assessed using the Preschool Age Psychiatric Assessment, performed by trained research assistants who were blind to genotyping information. |
Controls Exposed |
NA |
Replication Size |
None |
Result Summary |
Results: Race significantly moderated the association between genotype and PTSD. Specifically, the genotype associated with increased PTSD symptoms in one racial group had the opposite association in the other racial group. For AA children the met/met genotype was associated with more PTSD symptoms. However, for EA children, val allele carriers had more PTSD symptoms. Whereas every AA child with the met/met genotype met criteria for PTSD, none of the EA children with the met/met genotype did. This genetic association with COMT genotype, in both races but in opposite directions, was most associated with increased arousal symptoms. Conclusions: These findings replicate previous findings in participants of African descent, highlight the moderating effect of race on the association between COMT genotype and PTSD, and provide direct evidence that consideration of population stratification within gene-by-environment studies is valuable to prevent false negative findings. |
Potential Biomarker |
None |

Genetic result reported by this study

Normal genetic result reported by this study (count: 3)
Marker |
Phenotype |
Related Gene |
Statistical Values |
Author Comments |
Marker's Category |
rs4680
|
Total PTSD symptoms |
COMT |
In AA (n=104) group, COMT genotype, Wald X2=12.44, P-value=0.002. In EA (n=48) group, COMT genotye, Wald X2=10.99, P-value=0.004. |
Analyses within the AA group demonstrated that COMT genotype......
Analyses within the AA group demonstrated that COMT genotype was significantly associated with total PTSD symptoms. Individuals with met/met had significantly more PTSD symptoms than either other genotype (ps<0.014). Within the EA group, COMT genotype significantly predicted total PTSD symptoms. In this group, however, the val/val genotype group was associated with more PTSD symptoms, and significantly differed from both met groups (ps<0.013).
More...
|
Significant |
rs4680
|
PTSD category D symptom |
COMT |
In AA (n=104) group, COMT genotype, Wald X2=7.84, P-value=0.02. In EA (n=48) group, COMT genotye, Wald X2=6.19, P-value=0.045. |
A significant effect was found for Criterion D symptoms in A......
A significant effect was found for Criterion D symptoms in AA group and EA group separately.
More...
|
Significant |
rs4680
|
PTSD diagnosis |
COMT |
In African American, logistic regression, P-value=0.07; in European American, logistic regression, P-value=0.05. |
The logistic regression for COMT genotype by PTSD diagnosis ......
The logistic regression for COMT genotype by PTSD diagnosis did not terminate because of quasicomplete separation in the data (all AA children with met/met genotype met criteria for PTSD; no EA children with the met/met genotype met criteria for PTSD) (see Table 1).
More...
|
Non-significant |

Gene * Environment result reported by this study (count: 4)
Marker |
Phenotype |
Related Gene |
Environment |
Statistical Values |
Author Comments |
Marker's Category |
rs4680
|
PTSD category D symptom |
COMT |
Race |
Wald X2=10.47, P-value=0.005 |
A significant genotype by race interaction was found for Cri......
A significant genotype by race interaction was found for Criterion D symptoms. Given the repeated post-hoc tests, the family wise alpha level was adjusted to p<0.017 (dividing 0.05 by 3 [for the three symptom clusters]) to determine statistical significance. Even following this adjustment, the above-cited p value for the interaction of genotype and race for Criterion D symptoms remained statistically significant.
More...
|
Significant |
rs4680
|
Total PTSD symptoms |
COMT |
Race |
Wald X2=15.45, P-value<0.001 |
A significant COMT genotype by race interaction was found in......
A significant COMT genotype by race interaction was found in predicting total PTSD symptoms.
More...
|
Significant |
rs4680
|
PTSD category C symptom |
COMT |
Race |
Wald X2=4.22, P-value=0.12 |
Subsequent analyses within symptom clusters demonstrated tha......
Subsequent analyses within symptom clusters demonstrated that the genotype by race interaction was not significant for Criterion C symptoms.
More...
|
Non-significant |
rs4680
|
PTSD category B symptom |
COMT |
Race |
Wald X2=2.94, P-value=0.23 |
Subsequent analyses within symptom clusters demonstrated tha......
Subsequent analyses within symptom clusters demonstrated that the genotype by race interaction was not significant for Criterion B symptoms.
More...
|
Non-significant |