Complete nucleotide sequence of the 5′ noncoding region of human α- and β-globin mRNA

Abstract

The 5′ noncoding regions of human α- and β-globin mRNAs, 37 and 50 nucleotides in length, have been sequenced. A variation of the “plus and minus” gel technique described by Brownlee and Cartwright (1977) was used, and the results were cross-checked by the Maxam and Gilbert (1977) procedure. These studies completed the knowledge of all the noncoding region sequences of both mRNAs, and it was then possible to calculate their exact size. Human α- and β-globin mRNAs are 575 and 626 nucleotides in length, excluding the poly(A). Furthermore, because the coding and 3′ noncoding regions of the latter were known from previous studies ( Marotta et al., 1977 Proudfoot, 1977), the primary structure of human β-globin mRNA is now complete except for six ambiguities in the coding region. The human and rabbit 5′ noncoding region sequences are about 80% homologous. This suggests that they are under a moderate selective pressure.