Abstract:
Multiple endocrine neoplasia type 1 (MEN 1) is characterised by the combination of tumours
of the parathyroid, endocrine pancreas and anterior pituitary glands. In 1988 the MEN 1 gene
was mapped to chromosome 11q13 and it was cloned in 1997. This gene contains 10 exons and
extends across 9 Kb of genomic DNA; it encodes for a product of 610 amino acid named menin
whose function is unknown. We have studied 10 unrelated MEN 1 kindreds by a complete
sequencing analysis of the entire gene; mutations were identified in nine of them: five deletions,
one insertion, two nonsense mutation and a complex alteration consisting of a deletion and an
insertion that can be explained by a hairpin loop model. Two of the mutations have been
previously described; the other seven were novel, and they were scattered throughout the
coding sequence of the gene. As in previous series, no correlation was found between
phenotype and genotype.
