Table 1.
Detailed information for the analysis of fetus-specific microhaplotype alleles (paternal alleles) in cfDNA attained from 19 twin pregnancies.
| Case ID | cfDNA | Validated by Fetus Tissue | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| n. of Locus * | n. of Locus ** | n. of Assumed PA | Est. Lower FF % | Est. Higher FF % | Est. Combined FF % | n. of Locus † | n. of Locus ‡ | n. of Real PA †† | n. of PA Dropout | n. of Drop-In | PA Detection Rate | Lower FF % | Higher FF % | Combined FF % | Ratio § | |
| 2 | 37 | 8 | 45 | 5.21 | 8.53 | 13.74 | 37 | 8 | 45 | 0 | 0 | 100% | 6.13 | 8.06 | 14.18 | 1.316 |
| 3 | 33 | 3 | 36 | 3.84 | 5.81 | 9.65 | 33 | 3 | 36 | 0 | 0 | 100% | 3.43 | 5.82 | 9.25 | 1.695 |
| 5 | 36 | 6 | 42 | 5.94 | 7.88 | 13.82 | 36 | 5 | 41 | 0 | 1 | 100% | 6.08 | 7.95 | 14.03 | 1.308 |
| 6 | 37 | 8 | 45 | 6.13 | 10.35 | 16.48 | 37 | 8 | 45 | 0 | 0 | 100% | 6.77 | 10.62 | 17.40 | 1.569 |
| 7 | 37 | 6 | 43 | 7.28 | 20.29 | 27.58 | 37 | 6 | 43 | 0 | 0 | 100% | 7.17 | 18.33 | 25.50 | 2.558 |
| 8 | 31 | 3 | 34 | 4.51 | 11.02 | 15.53 | 32 | 4 | 36 | 2 | 0 | 94.44% | 3.66 | 8.66 | 12.32 | 2.369 |
| 9 | 40 | 6 | 46 | 3.53 | 6.88 | 10.41 | 41 | 6 | 47 | 1 | 0 | 97.87% | 3.90 | 7.52 | 11.42 | 1.928 |
| 10 | 36 | 10 | 46 | 8.01 | 12.02 | 20.03 | 36 | 10 | 46 | 0 | 0 | 100% | 8.33 | 11.18 | 19.51 | 1.341 |
| 12 | 37 | 3 | 40 | 7.35 | 12.14 | 19.49 | 36 | 3 | 39 | 0 | 1 | 100% | 6.30 | 10.37 | 16.67 | 1.646 |
| 14 | 36 | 7 | 43 | 6.46 | 9.47 | 15.93 | 36 | 7 | 43 | 0 | 0 | 100% | 6.75 | 8.79 | 15.54 | 1.301 |
| 15 | 37 | 6 | 43 | 3.03 | 5.40 | 8.43 | 37 | 5 | 42 | 0 | 1 | 100% | 3.72 | 4.71 | 8.44 | 1.265 |
| 16 | 34 | 6 | 40 | 4.00 | 7.16 | 11.16 | 34 | 6 | 40 | 0 | 0 | 100% | 4.04 | 6.81 | 10.85 | 1.685 |
| 17 | 39 | 7 | 46 | 2.99 | 6.40 | 9.39 | 40 | 7 | 47 | 1 | 0 | 97.87% | 3.33 | 5.70 | 9.03 | 1.715 |
| 1 | 33 | 0 | 33 | NA | NA | 11.90 | 33 | 0 | 33 | 0 | 0 | 100% | NA | NA | 11.90 | NA |
| 4 | 31 | 0 | 31 | NA | NA | 15.96 | 31 | 0 | 31 | 0 | 0 | 100% | NA | NA | 15.96 | NA |
| 11 | 33 | 0 | 33 | NA | NA | 9.05 | 33 | 0 | 33 | 0 | 0 | 100% | NA | NA | 9.05 | NA |
| 13 | 38 | 0 | 38 | NA | NA | 18.08 | 38 | 0 | 38 | 0 | 0 | 100% | NA | NA | 18.08 | NA |
| 18 | 31 | 0 | 31 | NA | NA | 9.34 | 31 | 0 | 31 | 0 | 0 | 100% | NA | NA | 9.34 | NA |
| 19 | 34 | 0 | 34 | NA | NA | 11.90 | 34 | 0 | 34 | 0 | 0 | 100% | NA | NA | 11.90 | NA |
*: locus with at least one assumed paternal allele (PA) observed in maternal cfDNA. **: locus with two assumed PAs observed in cfDNA, e.g., informative locus for a DZ pregnancy. †: locus with at least one real PA that should be detected in cfDNA without consideration of dropout and drop-in. ‡: locus with two real PAs that should be detected in cfDNA without consideration of dropout and drop-in. ††: the maximum number of PAs that should be detected in cfDNA without consideration of dropout and drop-in. §: higer fetal fraction (FF) vs. lower FF in DZ cfDNA. NA: not applicable.