Based on the previous observation of a very strong positive correlation between CR protein and CALB2 mRNA levels in 13 human MM cell lines, i.e. regulation mostly at the transcriptional level (see Fig. 1c in [25]), we assume levels of Calb2 mRNA to be low in mouse MM cell lines and MM tissue with no detectable CR protein levels. This evidence concerns the gene CALB2 and Miyoshi myopathy.