DNA Analysis Methods (TWGDAM), sent samples to 22 laboratories in October 1990 (Dennis Reeder, personal communication, 1991); 12 laboratories have reported so far. The greatest differences were reported to be slightly less than 5%. The preliminary results are encouraging, but need to be followed by more extensive reproducibility testing before the efficacy of a national network based on this method can be demonstrated. Moreover, the committee urges that laboratories participating in any national databank be required to participate in continuing proficiency and reproducibility studies (by carrying out blind measurements of samples sent from a common source), to ensure that reproducibility does not drift over time.
An analysis of the costs and benefits of establishing DNA databanks is problematic at best. Costs will depend on a number of variables, such as methods, numbers of loci used, and types and numbers of samples to be tested. Benefits will depend on the populations included in the databank and the likelihood of finding matches. Moreover, costs and benefits must be reckoned in both monetary and nonmonetary terms.
Nonmonetary costs can include the risk of loss of privacy and the misuse and abuse of genetic information. Nonmonetary benefits can include prevention of future crimes. Those diverse elements cannot be weighed except in the context of societal values.
Concerning monetary costs, it is helpful to recall the comparison between latent fingerprints and DNA profiles. Collection of fingerprints from identified persons is inexpensive and relatively easily accomplished by persons with minimal technical training and background. Samples cost perhaps a few dollars; the cost reflects the personnel time involved in taking and filing the fingerprints. Although sample collection is simple, fingerprint databanks require sophisticated and expensive computer hardware and software. A typical state automated fingerprint identification system can cost $10 million. In contrast, DNA typing is time-consuming, is expensive, and requires extensive education, training, and quality-assurance measures. With current RFLP methods, blood must be obtained by venipuncture at an estimated cost of $20/sample. Storage methods and costs depend on the number of samples and the form in which they are preserved (liquid or dried blood, extracted DNA pellet, buffy coat, etc.). In any case, freezers, cryotubes, and labor can cost another $20/sample for storage. The cost of RFLP analysis can be estimated from fees charged by private laboratories: about $100-150/sample.6 Thus, a single DNA profile can cost about $120-170, and constructing 10,000 DNA profiles could cost $1.2-1.7 million. However, DNA typing databanks do not require highly sophisticated or expensive computer hardware and software.