Polymorphism of the human MUC genes

Mucins encoded by the MUC genes share the common feature of having an extensive tandem repeat region that encompasses a large proportion of the coding sequence. In many of the genes this tandem repeat region shows a great deal of allelic length variation and recently studies have demonstrated person to person variation in pattern of nucleotide or amino-acid changes in the repeat units. The length and sequence variability will be discussed in this review, as will its role in disease susceptibility.