Molecular abnormalities responsible for IgH negativity in the 12 MM patients
| Abnormality . | MM-1 . | MM-2 . | MM-3 . | MM-4 . | MM-5 . | MM-6 . | MM-7 . | MM-8 . | MM-9 . | MM-10 . | MM-11 . | MM-12 . |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Biallelic JH deletion | − | − | − | − | − | − | − | + | − | − | − | − |
| IllegitimateIGH class switch | + | − | (+) | − | + | − | − | − | + | − | + | − |
| No IGH mRNA | − | + | + | − | − | − | ND | ND | ND | ND | ND | ND |
| Missing (VH)-DH-JH PCR product3-150 | − | +3-150 | ND | − | − | − | − | − | − | − | +3-150 | − |
| Only DH-JH with second allele deleted (or germline?) | − | − | ND | + | + | + | + | − | − | + | − | − |
| Nonfunctional VH-DH-JH | − | − | ND | − | − | − | − | − | − | − | + | − |
| Unexplained | − | − | − | − | − | − | − | − | − | − | − | + |
| Abnormality . | MM-1 . | MM-2 . | MM-3 . | MM-4 . | MM-5 . | MM-6 . | MM-7 . | MM-8 . | MM-9 . | MM-10 . | MM-11 . | MM-12 . |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Biallelic JH deletion | − | − | − | − | − | − | − | + | − | − | − | − |
| IllegitimateIGH class switch | + | − | (+) | − | + | − | − | − | + | − | + | − |
| No IGH mRNA | − | + | + | − | − | − | ND | ND | ND | ND | ND | ND |
| Missing (VH)-DH-JH PCR product3-150 | − | +3-150 | ND | − | − | − | − | − | − | − | +3-150 | − |
| Only DH-JH with second allele deleted (or germline?) | − | − | ND | + | + | + | + | − | − | + | − | − |
| Nonfunctional VH-DH-JH | − | − | ND | − | − | − | − | − | − | − | + | − |
| Unexplained | − | − | − | − | − | − | − | − | − | − | − | + |
Abbreviations: +, presence of abnormality; −, absence of abnormality; ND, not determined.
The single JH rearrangement in patient MM-2 and 1 of the 2 JH rearrangements in patient MM-11 could not be detected or identified by VH-JH or DH-JH PCR analysis, suggesting the presence of an aberrant JH rearrangement.