title: Use of stored newborn blood spots in research on birth defects: variation in retrieval rates by type of defect and infant characteristics.
abstract: Stored blood spots from state newborn screening programs represent a potential source of DNA for molecular genetics research on birth defects. The stored blood spots of cases and controls from an epidemiologic database on congenital heart defects were sought in the present study, which aimed to establish the feasibility of linking the data sources and to examine blood spot retrieval rates for selected cardiac defects. Blood spots were located on 341 of 522 infants (65%) with congenital heart defects and for 1,484 of 1,645 infants without birth defects (84%) born in Maryland during 1981-1989. Retrieval rates were low among infants with clinically severe lesions such as truncus arteriosus (26%) but were considerably higher in infants with coarctation of the aorta (62%), pulmonic valve stenosis (71%), and atrial septal defect (76%). Retrieval rates were significantly lower for premature and low-birth-weight infants than among full-term, normal-birth-weight infants. Retrieval rates did not vary significantly by gender, race, county of residence, or parental socioeconomic characteristics. These results demonstrate the feasibility of linking epidemiologic databases with stored newborn blood specimens, especially for normal infants and even for infants with certain congenital heart defects, but raise concerns about the adequacy of such methods to obtain stored specimens from premature infants and from those with severe heart defects.
authors.affiliation: Department of Epidemiology and Preventive Medicine, University of Maryland School of Medicine, Baltimore, USA.
authors.forename: C A
authors.initials: CA
authors.lastname: Loffredo
authors.forename: C K
authors.initials: CK
authors.lastname: Ewing
mesh_terms: D005260:Female; D006330:Heart Defects, Congenital / Q000097:blood*; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D008403:Mass Screening