Genetic linkage studies map the multiple endocrine neoplasia type 2 loci to a small interval on chromosome 10q11.2

We have carried out genetic linkage analyses using fifteen polymorphic loci in the pericentromeric region of chromosome 10 in families with the inherited cancer syndromes multiple endocrine neoplasia (MEN) type 2A or 2B. A highly polymorphic microsatellite from the locus D10S141 in q11.2 was found to be recombinant with respect to the disease locus in two individuals and defines a new proximal flanking marker for both MEN2A and 2B. An additional recombination provides evidence that the locus D10S94, also in q11.2, is the closet distal flanking marker for MEN2A. This localises the MEN2A gene to a small region of 10q11.2 flanked by the loci D10S141 and D10S94, which are separated by a sex-averaged genetic distance of 0.55 cM. The MEN2B gene maps to a larger region, flanked by D10S141 and RBP3.