Table 4.

Comparison of different frequently used sources of DNA in epidemiologic study settings

Buccal cells
NailsBloodMouth wash/salivaBuccal swap/cytobrushFast Technology for Analysis (FTA) cardHair with follicle
Typical collection amount (units)80 mgc3–15 mL4–20 mL1–3 swaps/brushes1 card3–6 hair with follicles
Mean DNA yield per unita0.03–0.4 μg/mg nail References:c, (8–10, 12, 15)20–60 μg/mL Reference: (17)0.4–23 μg/mL References: (18–25)1.3–32 μg/brush References: (19–21, 23–26)3–36 μg/card References: (19, 20)0.05–1.5 μg/hair with follicle Reference: (9)
Percentage human DNA (%)?94Reference: (24)34–68Reference: (24)11Reference: (24)?e?
DNA purity
 A260/A2801.5–1.7Reference:c, (10)1.8References: (19, 27)1.5–1.9References: (19–21, 23–25)1.1–2.0References: (19–21, 23–27)0.9–1.1References: (19, 20)1.8Reference: (27)
 A260/A2300.7 Reference:c1.4Reference: (19)0.8–1.9References: (19, 21)0.2References: (19, 21)0.2Reference: (19)?
Majority of DNA fragment sizes200 bp Reference:c, (9)>23 kb>23 kb Reference: (20)???
Success rate of approximately 200-bp fragment amplification (%)80–100 Reference:c, (11)100 Reference: (19)84–100 References: (19, 21, 23, 24, 28)23–100 References: (19, 21, 23, 24, 29)0–100 References: (19, 20, 29, 30)fReference: (31)
Contains high-molecular weight DNA (>23 kb) (−, +/−, or +)− Reference:c, (9)+ Reference: (9)+ References: (20, 32)+/− References: (9, 20, 24)− Reference: (20)− Reference: (31)
Suitability for WGA and subsequent genotyping (− or +)?++Reference: (33)+Reference: (34)+References: (30, 34)+bReferences: (31, 35)
Suitability for pediatric epidemiologic studies (− −, −, +, or ++)++− −− −++
Ease (in terms of invasiveness) of collection (− −, −, +, or ++)+ +− −+++
Response rate for participation (%)75 Reference: (2)31Reference: (19)67–72References: (19, 22)80Reference: (19)76Reference: (19)?
Self-administered collection (yes or no)YesNoYesYesYesYes
Ease (in terms of costs of materials, postage) of obtaining sample (− −, −, +, or ++)+ +− −+/−+/−+ +
Ease of tissue sample storage (− or +)+d+
  • aAs measured with NanoDrop/spectrophotometrically.

  • bWGA worked with GenomePlex, not with MDA.

  • cPresent results.

  • dDepends on collection method. Samples may be stable at room temperature for >1 year (Oragene; ref. 19).

  • eBecause cytobrushes or swaps are used to collect the buccal cells that are then transferred to the FTA card, it can be assumed that the FTA card contains the same percentage of human DNA, although FTA cards are treated to prevent microbial growth. Thus, the percentage of human DNA on FTA cards may be higher than that obtained from buccal swaps or brushes.

  • fOnly successful for freshly plucked hairs, not for hairs stored for 7–11 years.