Invasive procedures avoided if amniocentesis referrals follow sequencing test results
WEDNESDAY, Jan. 12 (HealthDay News) -- Multiplexed maternal plasma DNA sequencing analysis could be used in high-risk pregnancies to rule out fetal trisomy 21, rendering invasive diagnostic procedures unnecessary if referrals are based on sequencing results, according to a study published Jan. 11 in BMJ.
Rossa W.K. Chiu, M.B.B.S., Ph.D., from The Chinese University of Hong Kong, and colleagues studied 753 pregnant women at high risk for fetal trisomy 21 who underwent definitive diagnosis using full karyotyping. They sought to determine the efficacy of maternal plasma DNA sequencing in screening for fetal trisomy 21 among women with high-risk pregnancies who were advised to have amniocentesis or chorionic villus sampling. They used two protocols with different sample throughput levels of 2-plex and 8-plex sequencing.
The researchers found that the 2-plex sequencing detected trisomy 21 with 100 percent sensitivity and 97.9 percent specificity. The 8-plex sequencing detected 79.1 percent of the trisomy 21 fetuses with 98.9 percent specificity. They found the 2-plex protocol did not give false negative results. Researchers concluded that referrals for amniocentesis and chorionic villus sampling would drop by 98 percent if the decision to test was based on results from multiplexed maternal plasma DNA sequencing analysis.
"We show that fetal trisomy 21 could be detected in high-risk pregnancies with high sensitivity and specificity by means of multiplexed sequencing of maternal plasma
DNA," the authors write.
Several authors disclosed financial ties with biotechnology companies.