Globin mRNA Sequences: Analysis of Base Pairing and Evolutionary Implications

Over the past several years we attempted to develop in my laboratory general techniques for the sequence analysis of mammalian mRNAs (Salser et al. 1972, 1973, 1974; Paddock et al. 1974; Poon et al. 1974). Existing RNA sequencing techniques were poorly suited for this task, and our first approach was to use reverse transcriptase to make cDNA copies of the mRNAs so that DNA sequencing techniques could be employed (Salser et al. 1973). By analysis of RNA transcripts of the cDNA and the use of deoxysubstitution techniques, we were able to determine the sequences of substantial portions of the rabbit globin cDNAs and establish that reverse transcriptase gave high fidelity when used in this manner (Salser et al. 1973; Poon et al. 1974). These conclusions were independently confirmed by Marrotta et al. (1974), working with human globin cDNAs.