Chromosomal Aberrations Common to Three Types of Monoclonal Gammopathies

1. Chromosomal patterns in 24 patients with γG-, γA- and γM-type monoclonal gammopathies (MG) are described.

2. Significant chromosomal abnormalities were observed in all three types of monoclonal gammopathies. Abnormal chromosomes in the AB size range, or larger (MG-chromosomes), were present in five of seven patients with γM-MG, in three of three patients with γA-MG and in seven of 14 patients with γG-MG. Abnormalities in the smallest group C chromosomes (pair 12), consisting of missing chromosomes, extra chromosomes, or structural anomalies, were noted in all γM-MG patients, in two with γA-MG and in eight with γG-MG.

3. The literature dealing with chromosomal aberrations in primary macroglobulinemia (Waldenström) and myeloma has been reviewed, and the various abnormalities have been discussed.

4. These chromosomal abnormalities suggest a common denominator for the three types of monoclonal gammopathies, without implying either etiologic or pathognomonic specificity.