Genetic screening of newborns for sickle cell disease: Correlation of DNA analysis with hemoglobin electrophoresis

Abstract

Although DNA analysis based on the polymerase chain reaction (PCR) offers potential advantages for screening newborns for sickle cell disease, few data are available concerning the reliability of PCR-based tests for such screening. We describe a protocol for detecting the A, S, and C alleles of the β-globin gene in dried blood from phenylketonuria screening cards. This method is based on PCR and detection with allele-specific oligonucleotide probes. Results of a blind comparison of PCR analysis of the dried blood with hemoglobin electrophoresis of whole-blood samples agreed for 80 of 81 samples. The single discrepancy is probably not attributable to a failure of the PCR method, but rather to limitations of the electrophoresis method. The PCR method should be a highly accurate means of detecting β-globin alleles in routine genetic screening with dried blood already collected for (e.g.) phenylketonuria screening.