Table 2. The fetal DNA percentage estimated by the alterations of the genomic representation of the regions affected by microdeletion/microduplication, and the proportions of chromosome Y sequences in the maternal plasma.
| Fetal DNA percentage | |||
| Case | Fetal sex | By genomic representation of the affected chromosomal region(s) | By chr Y approacha |
| 01 | F | 10.5% | − |
| 02 | M | 17.4% | 21.5% |
| 03 | M | 9.2% | 13.7% |
| 04 | M | 17.8% | 20.3% |
| 05b | F | – | − |
| 06 | F | 10.9%/13.4%c | − |
a
The chr Y approach is only applicable for those cases with a male fetus.
b
For case 05, as the mother also carried the aberration, the genomic representation of the affected region in the maternal plasma could not be used to determine the fetal DNA percentage.
c
The former and latter figures represent the fetal DNA percentage estimated from the microduplication on chromosome 3 and the microdeletion on chromosome 4, respectively.