DNA-sequence analysis of amplified GPIbβ gene of an Iy^a-positive individual.

Polymerase chain reaction (PCR) products of the GPIbβ gene encompassing nucleotides 47-563 were subcloned in the plasmid vector pGEM-5Zf and sequenced on both strands. Nucleotide-sequences of 2 positive clones are shown. (A) The wild-type G in position 141 is changed to an A (arrow), predicting a glycine to glutamic acid (GGG→GAG) polymorphism at position 15 of the mature glycoprotein. (B) The sequence is identical to the published wild-type sequence for GPIbβ.20