TABLE 2.
SNP-array results of 5000 samples according to indications for prenatal testing.
| Indications | Numbera | Normal | Aneuploidy& Triploidyb | LOH | CNV | CNVc | |||
| P | LP | VOUS | LB | ||||||
| Anomaly on ultrasonography | 1055 | 890 (84.4%) | 66 (6.3%) | 2 (0.2%) | 97 (9.2%) | 40 (3.8%) | 7 (0.7%) | 29 (2.7%) | 21 (2.0%) |
| Advanced maternal age (≥35) | 1784 | 1591 (89.2%) | 74 (4.1%) | 10 (0.6%) | 109 (6.1%) | 23 (1.3%) | 6 (0.3%) | 48 (2.7%) | 32 (1.8%) |
| Abnormal result on maternal serum screening | 1199 | 1091 (91.0%) | 20 (1.7%) | 3 (0.3%) | 85 (7.1%) | 25 (2.1%) | 6 (0.5%) | 24 (2.0%) | 30 (2.5%) |
| Abnormal NIPT results | 515 | 325 (63.1%) | 116 (22.5%) | 3 (0.6%) | 71 (13.8%) | 9 (1.7%) | 6 (1.2%) | 37 (7.2%) | 19 (3.7%) |
| Otherd | 709 | 646 (91.1%) | 1 (0.1%) | 3 (0.4%) | 59 (8.3%) | 17 (2.4%) | 4 (0.6%) | 17 (2.4%) | 21 (3.0%) |
| All | 5000 | 4383 (87.7%) | 207 (4.1%) | 21 (0.4%) | 389 (7.8%) | 105 (2.1%) | 27 (0.5%) | 144 (2.9%) | 113 (2.3%) |
aAs more than one indication may be associated with each sample, the total number of listed five categories is more than 5000.
b2 cases of 69,XXX triploidy were identified in the group of anomaly on ultrasonography.
cCNVs were classified into four groups according to interpretation: P, pathogenic; LP, likely pathogenic; VOUS, variation of uncertain significance; LB, likely benign. For 28 cases with more than one CNV, 10 cases with 2 CNVs including a pathogenic CNV and a VOUS CNV were listed in the P group, and the rest 16 cases including 13 cases with 2 P CNVs, 3 cases with 2 VOUS CNVs, 1 case with 2 LB CNVs and 1 case with 3 LB CNVs.
dOther indications for prenatal testing include history of adverse pregnancy, parental genetic abnormalities, in vitro fertilization, medication use or toxic exposure during pregnancy, consanguineous marriages and parental anxiety.