Isolating Non-Persisting Fetal Cells
The CellScape team has solved the problem of isolating fetal cells from maternal blood and is developing what will soon be the most comprehensive noninvasive prenatal genetic test on the market. The Clarity Test analyzes genomic DNA from fetal cells using chromosomal microarrays, although a variety of genetic testing methods are possible.
Unique Fetal Cell-Specific Identifier
These images show three different views (under different lighting conditions) of one male fetal cell surrounded by maternal cells:
- In the left image, a Y chromosome (since it’s a male fetus) shows up as a single yellow Flourescent In-Situ Hybridization (FISH) dot inside the cell.
- In the middle image, in the same fetal cell as in the left image, a single X chromosome is seen as blue FISH dot. Notice that the surrounding maternal cells have two blue FISH dots because female cells have two X chromosomes.
- In the right image, the same fetal cell glows bright green while the maternal cells show very little green, showing that CellScape’s Fetal Identifier is specific for fetal cells.
CellScape Process for Collecting Non-Persisting Fetal Cells
The Clarity Test uses chromosomal microarray analysis (CMA) of fetal genomic DNA to detect a large but targeted set of known genetic disorders that currently cannot be detected without invasive testing. CMA is already used by many laboratories to analyze DNA from fetal cells collected via invasive procedures because CMA is able to detect far more abnormalities than karyotyping*; CellScape’s innovation will make this technology available to women noninvasively. In addition to all trisomies, the Clarity Test will detect the majority of chromosomal insertion and deletion syndromes (copy number variants, CNVs) identified as prenatally relevant by groups such as the American College of Medical Genetics (ACMG) and the International Standards for Cytogenomic Arrays (ISCA) Consortium.
* Recent landmark NICHD study (Wapner et al, 2012) demonstrates the most common prenatal diagnostic methods without chromosomal microarrays miss important genetic disorders and disabilities. See Wapner et al., NEJM, 367: 2175-2184, 2012. For more information (Link takes you to another website.)