Background Non-invasive prenatal testing (NIPT) using cell-free fetal DNA from maternal plasma for fetal aneuploidy identification is expanding worldwide. The objective of this study was to evaluate the clinical utility of NIPT for the detection of trisomies 21, 18, and 13 of high-risk fetus in a large Korean population. Methods This study was performed retrospectively, using stored maternal plasma from 1,055 pregnant women with singleton pregnancies who underwent invasive prenatal diagnosis because of a high-risk indication for chromosomal abnormalities. The NIPT results were confirmed by karyotype analysis. Results Among 1,055 cases, 108 cases of fetal aneuploidy, including trisomy 21 (n = 57), trisomy 18 (n = 42), and trisomy 13 (n = 9), were identified by NIPT. In this study, NIPT showed 100% sensitivity and 99.9% specificity for trisomy 21, and 92.9% sensitivity and 100% specificity for trisomy 18, and 100% sensitivity and 99.9% specificity for trisomy 13. The overall positive predictive value (PPV) was 98.1%. PPVs for trisomies 21, 18, and 13 ranged from 90.0% to 100%. Conclusion This study demonstrates that our NIPT technology is reliable and accurate when applied to maternal DNA samples collected from pregnant women. Further large prospective studies are needed to adequately assess the performance of NIPT.

This study attempted to identify where residents of public rental housing in Seoul want to move from now on and analyze factors which could affect their housing choices. To this end, the housing choices were classified into maintenance, other public rental housing, private housing except apartments and private apartments in order to analyze them on the basis of current and desired types of moving. The main findings are as follows. First, it was confirmed that most residents of public rental housing considered moving and housing choices were different from each resident. More specifically, those who were older, resided for a longer time or were much satisfactory for residence than others did not want to move but to stay. On the other hand, those who were rented monthly, earned less income or resided in non-apartments wanted more other public rental housing. Residents with higher educational levels and earnings tended to move to the private housing. In particular, households with more earnings preferred private apartments, while residents who have the increase in the income of the family did non-apartments. Next, it was found that discriminations and conflicts among residents in public rental housing or concerns about their children's education had an effect on choosing others types of housing. Based on these results, it is necessary to figure out the residential demand, support housing mobility for desired places and improve discrimination, conflict, and educational environment for the quality of life.