Prothrombin "Mexico City," an asymptomatic autosomal dominant prothrombin variant.

A functionally normal but structurally abnormal prothrombin variant was found in a Mexican family. Immunoisoelectricfocusing studies revealed that this variant has a more acidic isoelectric point (4.01) than normal prothrombin (4.

'Incomplete' pyroglobulin-gamma disease in a patient with osteosclerotic myeloma.

A 50-year-old female, heterozygous for beta-thalassaemia was found to have a lytic lesion surrounded by osteosclerotic tissue in the 1st lumbar vertebra. Aspiration of the lesion showed 100% atypical plasma cells. The bone marrow contained 17% myeloma cells.