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The Ed-digital PCR test directly informs on the presence and number of transgenes copies  inserted in the genome of CRISPR-edited cells
Thanks to its flexibility and ability to achieve precise targeting, the CRISPR system is a powerful gene editing tool for various molecular biology applications. Precise control of the transgene integration is a major challenge for human cell research biosafety. Despite the improvement of CRISPR specificity, a significant proportion of transgenes integrates at unintended sites. These off-target insertions can cause genomic alterations that may disrupt normal cell functions with dramatic consequences on research outcomes. Therefore, it is crucial to verify the transgene presence at the desired genome site using PCR or sequencing, and also to confirm the absence of any possible additional unwanted insertion using Ed-digital, Stem Genomics digital PCR test for transgene copy number quantification. Ed-digital services The Ed-digital test allows the detection of the number of transgene copies present in the genome of gene-edited cells using droplet digital PCR. Ed-digital targets common resistance cassettes (puromycin, neomycin) as well as the fluorescent reporter gene mCherry. Examples of Ed-digital applications in gene-edited induced pluripotent stem cell (iPSC) lines Analysis of transgene integration in iPSC lines (graph on the left): A. Determination of the number of neomycin gene copies in two iPSC samples. The first sample carries two copies and the second one single copy of the transgene. B. Determination of puromycin gene copies in two iPSC samples. The first one carries two copies and the other one displays mosaic integration (n=2.5) of the transgene. Discover the test and request a quote

iCS-digital: A method for monitoring hPSC genome integrity that detects more than 90% of recurrent genomic abnormalities. The test is rapid (2-3 days), convenient (full service), straightforward, and can be performed using cell culture supernatant. It is particularly suitable for the routine monitoring of cell lines in culture and for screening genetically stable clones (e.g., CRISPR-edited iPSC clones, patient-derived iPSC clones…).

straightforward method for monitoring hPSC genome integrity
Now online “Recurrent genetic abnormalities in human pluripotent stem cells: definition and routine detection in culture supernatant by targeted droplet digital PCR” by Assou et al. The unique features of human pluripotent stem cells (hPSCs) open new opportunities for disease modeling, drug discovery and the development of cell-based therapies. However, genetic abnormalities can accumulate during the generation, long-term maintenance or during genome editing of these cells. Therefore, it is crucial to detect these abnormalities as soon as they appear to guaranty the safe and proper use of hPSCs in clinical practice and in research. To address this issue, Assou et al. performed an exhaustive study by combining data from publications describing the occurrence of hPSC aberrations during in vitro culture. Based on this large meta-analysis, a test called iCS-digital (in culture supernatant-digital PCR) has been designed consisting in a panel of droplet digital PCR probes that target the most recurrent abnormalities identified by these studies. Thanks to the precision of the digital PCR technology, the iCS-digital test allows the sensitive, precise and absolute quantification of copy number variations (CNVs) and the detection of anomalies that are below the G-banding method resolution, especially the sub-karyotypic 20q11.21 hotspot. Using the iCS-digital test, Assou et al. could monitor cell integrity through regular screenings, and record the moment where genomic aberrations appeared. Furthermore, the iCS-digital test presents the advantage of using cell culture supernatant instead of intact cells as a DNA source, bypassing the inconvenience of dedicating a certain fraction of cell material for control quality testing. To conclude, Assou et al. demonstrated the interest of the iCS-digital test for routine hPSC screening, thanks to the simplicity of the collection procedure, the rapidity of the test, and the accuracy of the digital PCR technology. This innovative test can change how hPSC quality control is implemented for their use in basic research, regenerative medicine, and can contribute to secure genome editing workflows. The iCS-digital TM test is exclusively provided by Stem Genomics as a full service. For more information and quotations, please follow these links: Download the publication Discover the test and request a quote

The iCS-digital TM test was used to evaluate the genomic integrity of hiPSCs in the work punblished by Neri et al. in Nature Communications in April 2019: "Human pre-valvular endocardial cells derived from pluripotent stem cells recapitulate cardiac pathophysiological valvulogenesis". https://www.nature.com/articles/s41467-019-09459-5

Stem Genomics will attend the First France-USA Stem Cell Symposium that will take place on June 25th 2019, the day preceding the ISSCR meeting, at the Eli and Edythe Broad CIRM Center for Regenerative Medicine and Stem Cell Research at the University of Southern California, Los Angeles. We look forward meeting you there! Don't hesitate to request a meeting in advance.

new website Stem Genomics made by Caconcept
Stem Genomics has launched its new website and we are excited to present its new look. Our new website provides a clear message about who we are, what we stand for and about our solutions. The website also boasts a clean design and intuitive and consistent site-wide navigation system with improved menu functionalities that direct you to the most relevant information for your needs. It is also fully responsive on mobile devices, and the website pages are easy to navigate using a wide range of web browsers and portable devices.