Research article

Genomic organization of the 3′-region of the human MUC5AC mucin gene: additional evidence for a common ancestral gene for the 11p15.5 mucin gene family

Marie-Pierre BUISINE, Jean-Luc DESSEYN, Nicole PORCHET, Pierre DEGAND, Anne LAINE, Jean-Pierre AUBERT


The human mucin gene MUC5AC is mapped clustered with MUC2, MUC5B and MUC6 on chromosome 11p15.5. We report here the isolation and characterization of a genomic cosmid clone, designated ELO9, spanning the 3´-region of MUC5AC and the 5´-region of MUC5B, allowing us to conclude that MUC5AC and MUC5B have the same transcriptional orientation. We determined the genomic organization and the entire sequence of the 3´-region of MUC5AC. The comparative molecular analysis of MUC5AC and MUC5B points to a remarkable similarity in the size and the distribution of exons, and in the type of splice sites, supporting the notion that MUC5AC and MUC5B have evolved from a single common ancestral gene. The derivation of the four genes of the 11p15.5 mucin gene family from a single ancestral gene is discussed.