Abstract
During the past decade new procedures have been developed for the isolation of RNA from a few mL of freshly collected blood. This material is reverse transcribed and the resulting cDNA can be used for the determination of the ratios between different types of globin mRNA, namely α2/α1, α/ζ α/β, γ/β, ββ/βδβLepLep/β, and Gγ /Aγ - Details about these polymerase chain reaction-based methods are reviewed, and information about their usefulness in studying α-thalassemia, β-thalassemia, sickle cell anemia and other β-globin gene abnormalities, Hb Lepore heterozygosity, and heterozygosity for α2- or α1-globin gene mutations will be provided. The methods are also most useful in characterizing the mRNA types in single, in vitro cultured, BFU-E colonies; in colonies derived from cells of a Hb S heterozygote; for instance, the βA- and βs-mRNAs were present in all colonies and in about equal quantities, while many of those cells from a subject with a somatic cell mutant (Hb Costa Rica) contained βA-mRNA and no β-Costa Rica mRNA, and only a few had both types. The techniques described have considerable diagnostic value and offer a rather simple approach to the study of some of the listed diseases.