A context for the PI (which includes Ki67, a standard marker to determine the fraction of cycling cells) is provided by the fact that a PI>2 occurs in 97% of 33 HMCL, 70% of 30 relapsed MM tumors, 13% of 231 untreated tumors, and none of 16 normal plasma cell samples (Table 2). This evidence concerns the gene MKI67 and Miyoshi myopathy.