The National Registry of Genetically Triggered Thoracic Aortic Aneurysms and Cardiovascular Conditions (GenTAC): results from phase I and scientific opportunities in phase II.

BACKGROUND: Genetically triggered thoracic aortic conditions (GenTACs) represent an important problem for patients and their families. Accordingly, the National Heart, Lung, and Blood Institute established the first phase of its national GenTAC Registry in 2006. ENROLLMENT AND DIAGNOSES: Between 2007 and 2010, 6 enrolling centers established the GenTAC I Registry consisting of 2,046 patients (Marfan syndrome 576 [28.2%], bicuspid aortic valve disease 504 [24.6%], aneurysm or dissection age <50 years 369 [18%], and others). Biologic samples for DNA analyses (white blood cells or saliva) are available in 97%, and stored plasma is available in 60% of enrollees. RESULTS: Initial scientific inquiry using the GenTAC Registry has included validation studies of genetic causes for aortic syndromes, potential usefulness of transforming growth factor beta (TGFB) blood levels in Marfan subjects, and current surgical approaches to ascending aortic conditions. FUTURE OPPORTUNITY: The second phase of GenTAC will allow biannual follow-up of GenTAC I enrollees for up to 9 years, enrollment of an additional 1,500 subjects, further integration of imaging findings with clinical and genetic data through utilization of an imaging core laboratory, important validation of phenotype-genotype correlations through a phenotyping core laboratory, and integration of a scientific advisory committee to help define the full range and depth of the Registry's scientific capabilities. The registry resources are available to the external scientific community through an application process accessible at https://gentac.rti.org.

Blood spots as an alternative to whole blood collection and the effect of a small monetary incentive to increase participation in genetic association studies.

BACKGROUND: Collection of buccal cells from saliva for DNA extraction offers a less invasive and convenient alternative to venipuncture blood collection that may increase participation in genetic epidemiologic studies. However, dried blood spot collection, which is also a convenient method, offers a means of collecting peripheral blood samples from which analytes in addition to DNA can be obtained. METHODS: To determine if offering blood spot collection would increase participation in genetic epidemiologic studies, we conducted a study of collecting dried blood spot cards by mail from a sample of female cancer cases (n = 134) and controls (n = 256) who were previously selected for a breast cancer genetics study and declined to provide a venipuncture blood sample. Participants were also randomized to receive either a $2.00 bill or no incentive with the blood spot collection kits. RESULTS: The average time between the venipuncture sample refusal and recruitment for the blood spot collection was 4.4 years. Thirty-seven percent of cases and 28% of controls provided a dried blood spot card. While the incentive was not associated with participation among controls (29% for $2.00 incentive vs. 26% for no incentive, p = 0.6), it was significantly associated with participation among the breast cancer cases (48% vs. 27%, respectively, p = 0.01). There did not appear to be any bias in response since no differences between cases and controls and incentive groups were observed when examining several demographic, work history and radiation exposure variables. CONCLUSION: This study demonstrates that collection of dried blood spot cards in addition to venipuncture blood samples may be a feasible method to increase participation in genetic case-control studies.