Sample bias among women with retained DNA samples for future genetic studies.
OBJECTIVE
To evaluate whether women who agree to future use of their biologic specimens for genetic studies reflect the larger study population from which they are derived.


METHODS
Women were questioned as to the future disposition of their maternal and fetal DNA samples upon enrollment in a multicenter, observational study originally designed to identify factor V Leiden mutation carriers and prospectively ascertain the estimated rate of pregnancy-related venous thromboembolism and adverse pregnancy outcome. Univariate and multivariate analyses was carried out on the 5,003 of 5,188 enrolled women who indicated their desire regarding future disposition of their DNA samples.


RESULTS
Among these 5,003 women, 20.1% desired that their samples be discarded and not available for future genetic studies. Multivariate analysis demonstrated that women who agreed to subsequent use of samples were less likely African-American (odds ratio [OR] 0.6, 95% confidence interval [CI] 0.4-0.7) or Hispanic (OR 0.4, 95% CI 0.3-0.5), and more likely to use tobacco (OR 1.2, 95% CI 1.0-1.6) than those who desired that their samples be discarded.


CONCLUSIONS
Genetic samples from women agreeing to their use in a sample repository may not be representative of the index study cohort. This should be considered in their subsequent interpretation and generalizability.


METHODS
III.
Aagaard-Tillery
Kjersti
K
Department of Obstetrics and Gynecology, University of Utah School of Medicine, Salt Lake City, Utah 84132, USA. kjersti131@prodigy.net
Sibai
Baha
B
Spong
Catherine Y
CY
Momirova
Valerija
V
Wendel
George
G
Wenstrom
Katharine
K
Samuels
Philip
P
Cotroneo
Margaret
M
Moawad
Atef
A
Sorokin
Yoram
Y
Miodovnik
Menachem
M
Meis
Paul
P
O'Sullivan
Mary J
MJ
Conway
Deborah
D
Wapner
Ronald J
RJ
D000328:Adult; D015986:Confounding Factors, Epidemiologic; D004247:DNA / Q000032:analysis*; D005006:Ethnicity; D005165:Factor V / Q000235:genetics; D005260:Female; D036281:Genetic Research; D005820:Genetic Testing / Q000523:psychology*; D006801:Humans; D007258:Informed Consent; D015999:Multivariate Analysis; D017354:Point Mutation; D011446:Prospective Studies; D015983:Selection Bias
C095381:factor V Leiden; D005165:Factor V; D004247:DNA