The impact of maternal plasma DNA fetal fraction on next gener ation sequencing tests for common fetal aneuploidies
8%), all 3 sex chromosome aneuploidies
were called correctly, and there was 1 false-negative sex chromosome result called (63).
Identification of fetal aneuploidies
from targeted cfDNA sequencing can be achieved either by quantitative counting or by genotype analysis of targeted single-nucleotide polymorphisms (SNPs).
The NATUS algorithm was able to correctly identify fetal aneuploidies
in all samples that passed the quality threshold, thus demonstrating 100 percent sensitivity and 100 specificity with a redraw rate of approximately 6 percent.
Some of the tests use massively parallel sequencing, which can be used to "look at everything," including sex chromosome aneuploidies
, although most laboratories use software that masks all but the results of interest.
Can you briefly describe how next-generation sequencing (NGS) (7) has been applied to the detection of chromosomal aneuploidies
with cell-free fetal DNA?
Paternal contribution to these aneuploidies
range from 10% to 100%, depending on the specific chromosome involved (7).
It is important for physicians to be able to detect common and severe aneuploidies
and microdeletion syndromes quickly and accurately so that they can work with expectant parents and clinicians to modify the management of the pregnancy and create the best possible healthcare support network for the baby and parent.
The MaterniT21 PLUS test, by contrast, reports both common and rare fetal chromosomal abnormalities-from trisomies 21, 18 and 13 to fetal sex aneuploidies
, trisomies 16, 22, fetal gender and select microdeletions.
Noninvasive prenatal diagnosis of common fetal chromosomal aneuploidies
by maternal plasma DNA sequencing.
DALLAS - Chromosomal microarray, or CMA, is as effective as karyotyping for identifying common aneuploidies
during routine and high-risk prenatal screening, and it also provides clinically significant and relevant information in patients with a normal karyotype, according to findings from a prospective study involving more than 4,400 women.
The genome-wide methylation analysis identified more than 3,000 differentially methylated regions with approximately 90% confirmation; study results showed proof-of-concept for the sensitive detection of aneuploidies