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Published on: June 10, 2018
Comparison of methods for collection of DNA samples by mail in the Black Women's Health Study
Yvette C Cozier1, Julie R Palmer, Lynn Rosenberg
1Slone Epidemiology Center, Boston University School of Public Health, Boston, MA 02215, USA. ycozier@slone.bu.edu
Purpose:
The authors compared approaches to participants and methods of collecting buccal cell samples by mail in the Black Women's Health Study, a follow-up study of geographically dispersed African-American women. Outcomes of interest were within group participation rates, yield of DNA, and PCR success.
Methods:
Six hundred fifty six participants were randomized to four groups: Groups 1 and 2 used the cheek swab method and Groups 3 and 4 used the mouthwash swish method. Groups 1 and 3 were mailed collection kits together with consent forms, whereas Groups 2 and 4 were mailed a kit only after returning a signed consent.
Results:
Participation rates were similar regardless of the method used for sample collection or mailing of the kits: samples were returned by 40% of Group 1, 37% of Group 2, 36% of Group 3, and 35% of Group 4. The median DNA yield was 3693 ng/sample for the swab method and 10,077 ng/sample for the mouthwash swish method (p<0.001). PCR analyses were successful in 98% of mouthwash samples and 94% of swab samples.
Conclusion:
Because of its higher yield of DNA, the mouthwash swish method is preferable for collection of buccal cell samples by mail.
