Low frequency of PIM3 gene in patients with monoclonal gammopathies.

The distribution of PI (protease inhibitor) phenotypes and PI M subtypes was studied in 200 patients with monoclonal gammopathies and 320 healthy blood donors by isoelectric focusing in thin-layer polyacrylamide gels, pH range 4-5. The distribution of PI phenotypes and gene frequencies in the patients differed significantly from the corresponding values found in the blood donors, as shown by the chi 2 test (chi 2 = 16.5, p = 0.02 and chi 2 = 17.6, p = 0.0014, respectively). A lower frequency of the M3 variant was observed in patients, both in homozygous (PI M3) and heterozygous forms (PI M1M3 and PI M2M3). No significant difference between PIz allele frequencies in patients and healthy controls was found.