NF1 gene dosage in bone marrows of children with NF1 and malignant myeloid disorders
. | . | . | . | Parental origin . | . | . | . | |
|---|---|---|---|---|---|---|---|---|
| Patient no. . | Sex . | Age at onset, mo . | Diagnosis . | NF1 mutation . | LOH at NF1 locus . | NF1 gene dosage value*† . | Predicted NF1 gene copy no.‡ . | |
| 1 | M | 9 | MPS | Paternal | Maternal | 0.99 | Disomy | |
| 2 | M | 10 | AML | Paternal | Maternal | 0.93 | Disomy | |
| 3 | M | 24 | Monosomy 7 | Unknown | Maternal | 0.96 | Disomy | |
| 4 | M | 14 | JMML | Maternal | Paternal | 0.86 | Disomy | |
| 5 | F | 30 | JMML | Maternal | Paternal | 0.94 | Disomy | |
| 6 | M | 10 | JMML | Maternal | Paternal | 0.87 | Disomy | |
| 7 | M | 5 | Monosomy 7 | Maternal | Paternal | 0.90 | Disomy | |
| 8 | F | 18 | MPS | Paternal | Maternal* | 0.85 | Disomy | |
| 9 | M | 60 | JMML | Maternal | Paternal | 0.57 | Monosomy | |
| 10 | M | 19 | Monosomy 7 | De novo | Maternal* | 0.48 | Monosomy | |
. | . | . | . | Parental origin . | . | . | . | |
|---|---|---|---|---|---|---|---|---|
| Patient no. . | Sex . | Age at onset, mo . | Diagnosis . | NF1 mutation . | LOH at NF1 locus . | NF1 gene dosage value*† . | Predicted NF1 gene copy no.‡ . | |
| 1 | M | 9 | MPS | Paternal | Maternal | 0.99 | Disomy | |
| 2 | M | 10 | AML | Paternal | Maternal | 0.93 | Disomy | |
| 3 | M | 24 | Monosomy 7 | Unknown | Maternal | 0.96 | Disomy | |
| 4 | M | 14 | JMML | Maternal | Paternal | 0.86 | Disomy | |
| 5 | F | 30 | JMML | Maternal | Paternal | 0.94 | Disomy | |
| 6 | M | 10 | JMML | Maternal | Paternal | 0.87 | Disomy | |
| 7 | M | 5 | Monosomy 7 | Maternal | Paternal | 0.90 | Disomy | |
| 8 | F | 18 | MPS | Paternal | Maternal* | 0.85 | Disomy | |
| 9 | M | 60 | JMML | Maternal | Paternal | 0.57 | Monosomy | |
| 10 | M | 19 | Monosomy 7 | De novo | Maternal* | 0.48 | Monosomy | |
Clinical descriptions, LOH, and NF1 mutation analyses have been reported previously for most of the patients.17-19
Data from this study employing quantitative PCR at NF1 gene segment
Measured in unfractionated bone marrow cells except in patients 3 and 9, for whom leukemic cells in peripheral blood were used
Predicted gene copy number based on NF1 gene dosage values. Validation of the assay on nontumor DNA demonstrated that NF1 disomy gave dosage values of 0.98 ± 0.08 SD, while monosomy gave values of 0.45 ± 0.04 SD. A range of 2 SD was used to approximate a 95% confidence interval. Therefore, values from 0.82 to 1.14 predicted disomy, and values from 0.37 to 0.53 predicted monosomy