Genetic and clinical analysis in 10 Spanish patients with multiple endocrine neoplasia type 1

Multiple endocrine neoplasia type 1 (MEN 1) is characterised by the combina tion of tumours of the parathyroid, endocrine pancreas and anterior pituita ry 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 gen omic DNA; it encodes for a product of 610 amino acid named menin whose func tion is unknown. We have studied 10 unrelated MEN 1 kindreds by a complete sequencing analysis of the entire gene; mutations were identified in nine o f 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 describe d; the other seven were novel, and they were scattered throughout the codin g sequence of the gene. As in previous series, no correlation was found bet ween phenotype and genotype.