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Rearrangements of the red-cell membrane glycophorin C (sialoglycoprotein beta) gene. A further study of alterations in the glycophorin C gene.

ABSTRACT: We have cloned portions of the glycophorin C (sialoglycoprotein beta) gene from individuals with red cells of normal, Gerbich and Yus phenotypes. The clones contain up to three exons of the glycophorin C gene (designated exons 2, 3 and 4). Analysis by restriction mapping and DNA sequencing confirmed that the deletions causing the Gerbich and Yus phenotypes are located entirely within the glycophorin C gene. Sequencing of the normal gene showed that not only do exon 2 and exon 3 have related DNA sequences, but also that both the 5' and 3' flanking intronic DNA sequences are almost identical. The two variant genes each lack a different exon: the Yus type gene lacks exon 2, whereas the Gerbich-type gene lacks exon 3. We suggest that the observed deletions are due to recombination between the regions of homologous intronic repeats. We also provide evidence that an unequal cross-over mechanism may be responsible for a number of observed glycophorin C gene rearrangements, including an insertion mutation in Lewis II (Lsa)-type red cells that has not previously been reported.

SUBMITTER: High S

PROVIDER: S-EPMC1133227 | biostudies-other | 1989 Aug

REPOSITORIES: biostudies-other

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Genetic variants of human red-cell membrane sialoglycoprotein beta. Study of the alterations occurring in the sialoglycoprotein-beta gene.

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2015-01-01 | GSE44134 | GEO

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