Positional Cloning.

   RFLP  fragments  from  many  chromosomes were used to map the locus of
   type 1 neurofibromatosis (NF1), an autosomal dominant disorder.

   NF1 patients exhibit a 1.9-kb RFLP fragment that segregates with other
   RFLP marker that had been assigned to chromosome 17.

   The  NF1  locus is subsequently mapped to a region near the centromere
   of chromosome 17.