NIPT

Harmony Test Targeted Technology - DANSR

Digital Analysis of Selected Regions (DANSR)

DANSR technology specifically targets just the chromosomes of interest for deep, directed analysis.1-2 In contrast, the majority of data generated by expansive (and expensive) whole genome sequencing has no relevance to aneuploidy screening.3

In practice, DANSR technology significantly improves assay efficiency, reduces overall test cost and provides for optimally streamlined workflow.1,2

DANSR APPROACH

●      Specific chromosomes of interest are targeted by hundreds of DANSR analyses

●      Eliminates lengthy and time-consuming whole genome data generation2

DANSR BENEFITS

●      Streamlined workflow

●      Cost-efficiency

Single Nucleotide Polymorphism (SNP) Analysis for Fetal Fraction

Because NIPT cannot provide reliable results on blood samples with a fetal chromosome fraction less than 4%,5 an accurate approach to fetal fraction measurement is essential.

The Harmony Test uses SNPs to analyze and report fetal fraction for every sample. SNPs are the most common type of genetic variation between individuals, with a normal occurrence of one in every 300 nucleotides.6 Detection of these variations allows for reliable determination of fetal fraction.

●      Hundreds of SNPs are analyzed

●      Fetal fraction is determined for every sample

BENEFITS

●      Ensures sufficient fetal fraction for accurate NIPT

●      Eliminates the potential of NIPT results based on maternal cfDNA

The importance of fetal fraction accuracy was highlighted when researchers submitted the blood of two non-pregnant women for non-invasive prenatal testing at five different laboratories.7

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PATIENT 1

 

PATIENT 2
 

LABORATORY TEST

RESULTS

DETAILS

RESULTS

Details

Harmony Prenatal Test

No

Insufficient fetal cfDNA

No

Insufficient fetal cfDNA

Panorama

No

Unable to report due to low fetal fraction (0.6%)

No

Unable to report due to low fetal fraction (0.6%)

MaterniT21

Yes

4.3% fetal fraction, negative screen consistent with female fetus

Yes

3.9% fetal fraction, negative screen consistent with female fetus

Illumina-based NIPT

Yes

XX fetus, no aneuploidy detected

Yes

XX fetus, no aneuploidy detected

Illumina-based NIPT

Yes

XX fetus, no aneuploidy detected

Yes

XX fetus, no aneuploidy detected

Three out of five laboratories reported a negative screen consistent with a female fetus.

●      One laboratory reported, and quantified, a fetal fraction too low to perform NIPT.

●      Only the Harmony NIPT laboratory accurately reported insufficient fetal fraction with no misleading results.*

*Blinded samples. NIPT Brand results identified by results reporting convention.

Custom Microarray Precision

DANSR is a proprietary analysis highly targeted for the specific chromosomes of interest. As such, it is extremely well-suited to take advantage of the benefits of microarray technology.

Incorporation of microarray technology results in decreased variance in chromosome cfDNA counts, increased fetal fraction precision, lower cost and dramatically reduced time-to-result.2

MICROARRAY APPROACH 2

●      Improves assay precision two-fold compared to next-generation sequencing

●      Increases SNP assays for fetal fraction approximately 3-fold compared to next-generation sequencing, making the fetal fraction measurement more accurate

 

MICROARRAY BENEFITS 2

●      Significantly increased assay precision

●      Lower test cost

●      Dramatically decreased time-to-result

FORTE ALGORITHM

FORTE is the proprietary Harmony Test algorithm. FORTE, which is included in the AcfS Software, incorporates individual patient factors including fetal fraction, maternal age, and gestational age to clearly distinguish between high and low probability results.1 Compared with commonly utilized Z-Statistic scoring, FORTE provides greater discrimination between true positive and true negative results.5

FORTE APPROACH

●      Targeted analysis plus patient factors generate an individually weighted probability assessment1

●      Individualized assessment allows for greater discrimination between high- and low-probability results8

FORTE BENEFITS

  • Clearer separation between low and high probability results provides greater confidence even at low fetal fraction 

References

1.       Sparks et al. Prenat Diagn. 2012 Jan;32(1):3-9.

2.       Juneau et al. Fetal Diagn Ther. 2014. 36(4)282-6.

3.       Jensen et al. PLoS One. 2013;8(3):e57381. 

4.       https://ghr.nlm.nih.gov/chromosome

5.       Ashoor et al. Ultrasound Obstet Gynecol. 2013 Jan; 41(1):26-32.

6.       https://ghr.nlm.nih.gov/primer/genomicresearch/snp. Accessed April 24, 2017.

7.       Takoudes and Hamar. Ultrasound Obstet Gynecol 2015; 14:112-116. 

8.       Ashoor et al. Am J Obstet Gynecol. 2012 Apr;206(4):322.e1-5.