Tags: Patient Perspectives, 2023, Australia, RAAs, CNVs

• 219 women in Western Australia were surveyed regarding the use of NIPT to detect multiple different single gene and chromosome conditions.
• Most women (96%) supported expanded NIPT for single gene and chromosome conditions as long as the test does not pose any risk to the pregnancy and can provide relevant medical information about the fetus. Most women (80%) indicated that expanded NIPT should be available at any stage during pregnancy and 68% indicated that the cost of the test would influence their participation in testing.

The post Western Australian women’s expectations for expanded NIPT-An online survey regarding NIPT for single gene, recessive and chromosomal conditions appeared first on Global NIPT Consortium.

Tags: Clinical Experience / Clinical Utility, 2023, Australia, RAAs, CNVs

• Retrospective study of all cases with NIPT from 3 tertiary providers of obstetric ultrasound using NIPT as a first line screening test over a 4-year period.
• “The LTFU [late first trimester ultrasound] findings significantly altered the PPV of the NIPT result for trisomies 13, 18 and 21, monosomy X (MX) and rare autosomal trisomies (RATs), but not for the other sex chromosomal abnormalities or segmental imbalances (>7 Mb). An abnormal LFTU increased the PPV close to 100% for trisomies 13, 18 and 21, MX and RATs. The magnitude of the PPV alteration was highest for the lethal chromosomal abnormalities.”
• “Conclusions: LTFU after a high-risk NIPT result can alter the PPV of many chromosomal abnormalities, assisting counselling regarding invasive prenatal testing and pregnancy management.”

The post Late first-trimester ultrasound findings can alter management after high-risk NIPT result. appeared first on Global NIPT Consortium.

Tags: Clinical Experience / Clinical Utility, 2022, Australia, RAAs, CNVs

• “Among 23,857 women screened, there were 93 high-risk results for RATs (0.39%) and 82 for SIs [structural imbalances] (0.34%). The PPVs were 3.8% (3/78, 95% CI 0.8%-10.8%) for RATs and 19.1% (13/68, 95% CI 10.6%-30.5%) for SIs. If fetuses with structural anomalies were also counted as true-positive cases, the PPV for RATS increased to 8.5% (7/82, 95% CI 3.5%-16.8%). Among 85 discordant cases with birth outcomes available (65.4%), discordant positive RATs had a significantly higher proportion of infants born below the 10th and 3rd birthweight percentiles than expected (19.6% (p = 0.022) and 9.8% (p = 0.004), respectively), which was not observed in the SI group (2.9% < 10th (p = 0.168) and 0.0% <3rd (p = 0.305)).”

The post Cell-free DNA screening for rare autosomal trisomies and segmental chromosome imbalances. appeared first on Global NIPT Consortium.

Tags: Laboratory Experience / Laboratory Performance, 2021, Australia, RAAs, CNVs

• Study of GW-NIPT in 2335 frozen plasma samples to detect GW chromosomal anomalies including common trisomies, SCAs, RAAs, and partial deletions and duplications.
• “Genome-wide screening analysis including known mosaics correctly classified 27/28 RAAs and 20/27 partial deletions/duplications with a specificity of 99.80% for both anomalies, and an overall genome-wide specificity for all anomalies of 99.34%.”
• ”With an overall genome-wide clinical specificity for any anomaly of 99.34%, this genome-wide screen allows for detection of a broad range of chromosomal anomalies while retaining a clinical specificity far superior to the ~5% false-positive rate of serum screening.”

The post Performance of a Paired-End Sequencing-Based Noninvasive Prenatal Screening Test in the Detection of Genome-Wide Fetal Chromosomal Anomalies. appeared first on Global NIPT Consortium.

Tags: Clinical Experience / Clinical Utility, 2020, Australia, CNVs

• This pilot series comprises a retrospective analysis of GW-NIPS and clinical outcome data from 42 singleton pregnancies where one parent carried a balanced reciprocal translocation. GW-NIPS was performed between August 2015 and March 2018. Inclusion criteria required at least one translocation segment to be ≥15 Mb in size.
• “Forty samples (95%) returned an informative result; 7 pregnancies (17.5%) were high risk for an unbalanced translocation and confirmed after diagnostic testing. The remaining 33 informative samples were low risk and confirmed after diagnostic testing or normal newborn physical exam. Test sensitivity of 100% (95% confidence interval [CI]: 64.6-100%) and specificity of 100% (95% CI: 89.6-100%) were observed for this pilot series.”
• “We demonstrate that GW-NIPS is a potential option for a majority of reciprocal translocation carriers. Further confirmation of this methodology could lead to adoption of this noninvasive alternative.”

The post Genome-wide noninvasive prenatal screening for carriers of balanced reciprocal translocations. appeared first on Global NIPT Consortium.

Tags: Clinical Experience / Clinical Utility, 2018, Australia, RAAs

• This publication demonstrated the importance of screening all autosomes using NIPT. Of the cases analyzed, 1/835 (0.12%) were identified to have a rare autosomal trisomy. Of these cases, 68% were associated with adverse outcomes, that included pregnancy loss, prematurity, true fetal mosaicism, growth restriction, and fetal structural anomalies.

The post Rare autosomal trisomies: Important and not so rare. Prenat Diagn appeared first on Global NIPT Consortium.