Introduction Genetic studies depend on well-characterized phenotypes to establish relationships between disease and genetic mutations. Researchers typically study and collect DNA from a single group of subjects and may not have ready access to other study populations that may be excellent controls for their study population. The University of Florida General Clinical Research Center (UFGCRC) evaluated approximately 1000 new study subjects in 2003-2004. To allow GCRC researchers to expand their gene-based studies beyond their own study groups the GCRC established a DNA bank that enrolled subjects admitted to the GCRC inpatient and outpatient facilities.
Methods Following consent, up to 20 mL of whole blood was obtained and the attending physician designated up to 10 ICD-9 codes that best characterized the study subject. A secure database, reporting and tracking system was developed using MySQL/PHP and Freezerworks 1.0.4 (DataWorks Development, Mountlake Terrace, WA). Demographic information was collected from all study subjects. DNA was extracted from whole blood using a Gentra Puregene DNA extraction kit (Minneapolis, MN). DNA concentration and purity were established by spectrometry at UV wavelengths of 260 and 280 nm. The quality of extracted DNA was further determined by demonstrating that the alpha-1-antitrypsin gene could be amplified using Taq polymerase (Promega, Madison, WI).
Results To date 324 subjects have consented to participate in the GCRC DNA bank. Twenty-two percent of the subjects are male. Ethnicity-race percentages are 71.3% Caucasian, 21% African-American, 6.5% Hispanic and 1.6% are Asian. Age distribution is 22.8% are>50 years old, 23.5% age 36-50 years, 45.7% age 20-35 years and 8% are less that 20 years old. Disease categories included 36% normal, 18.2% endocrine, 13.3% cardiovascular, 10.5% gastrointestinal, 9.3% genital-urinary, 4.9% respiratory, 7.7% infectious disease, 33.3% rheumatology and 14.2% other diseases. The mean DNA concentration is 306 ± 208 μg/mL (n = 212), DNA purity 1.98 ± 0.07 (A260/A280), mean amount of DNA/subject, 839 μg. The alpha-1-antitrypsin gene was successfully amplified in 99% to the subjects evaluated to date.
Conclusion The GCRC has established a new resource for GCRC investigators to utilize for the purpose extending their gene-based research. Access to the sample collection is through a GCRC Advisory subgroup panel, which upon approval of a brief application provides the investigator with normal and disease specific DNA samples.