Mild spondyloepiphyseal dysplasia (Namaqualand type): genetic linkage to the type II collagen gene COL2A1.

Namaqualand spondyloepiphyseal dysplasia (NSED) is a mild autosomal dominant form of spondyloepiphyseal dysplasia in which changes are maximal in the femoral capital epiphyses and the vertebral bodies. The condition is present in a large multigeneration South African family, and it is clinically important by virtue of severe progressive degenerative osteoarthropathy of the hip joint, which frequently necessitates prosthetic joint replacement in adulthood. Linkage studies using molecular markers have shown that the loci for the NSED and type II collagen genes are linked (LOD score 7.98 at a recombination fraction of .00).     

Protein identification by in-gel digestion and mass spectrometric analysis

This protocol details a method for the identification of proteins that have been separated by gel electrophoresis. In-gel digestion of the protein bands with trypsin followed by quadrupole ion-trap or other triple quadrupole mass spectrometry techniques is described. The proteins can be identified by database searching of the mass fingerprint of the intact peptides and of the characteristic fragment masses produced by tandem mass spectrometry.