Table 1.
Prenatal BWS test results of 301 fetuses with omphalocele
| Sample type | Total number | BWS positivea | BWS negativeb |
|---|---|---|---|
| Amniocytes (cultured) | 184 | 32 | 152 |
| Amniocytes (direct) | 1 | 0 | 1 |
| CVS (cultured) | 101 | 5 | 96 |
| CVS (direct) | 1 | 0 | 1 |
| POC/fetal tissue (cultured) | 5 | 1 | 4 |
| Extracted DNA (CVS or amniocytes) | 9 | 2 | 7 |
| Total | 301 (100%) | 40 (13.3%) | 261 (86.7%) |
BWS Beckwith-Wiedemann syndrome
aAmong the 40 positive samples, 23 were initially only tested for the IC2 locus and IC1 methylation was determined retrospectively for this study; of these, 4 did not have sufficient DNA to analyze the IC1 locus
bOf the 261 negative samples, 103 were assessed for both IC2 and IC1 loci, whereas 158 were tested for the IC2 locus only