Frequently Asked Questions

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The  validity of research data relies heavily on the identity of the cell  line used in testing.  According to the American Type Culture Collection  (ATCC) Standards Development Organization Workgroup (SDO) ASN-0002 [4],  only 33% of researchers test the authenticity of their cell lines.   Cell line authentication puts your mind at ease about all the hard work  and time you have put into your research. Retractions hurt the  reputation of the researcher and the research institution that supports  the research. 

If your cell line was purchased from a repository, an authentication report may have been included with your purchase. 

However,  cell lines should be regularly authenticated after purchase. It is  recommended that cell lines be validated every 1-2 months during active  growth.  In addition, many journals now have guidelines for cell line  authentication testing prior to publication. 

Contamination  and misidentification can happen in any lab; it is therefore crucial to  authenticate your cell cultures periodically so that you are sure you  are working with the genuine cell lines as your experiments progress.

Labcorp has  over 30 years of experience in human DNA identification. Our DNA  laboratory provides high quality DNA tests including parentage, family  relationship, and human DNA identity tests, as well as research services  such as cell line authentication, MSI testing and mycoplasma  contamination detection testing. 

Visit our "About Us" page for more information.

Yes!  There are researchers who have lost years of work to problems such as  cell line cross-contamination or misidentification.  On August 15, 2010,  the authors of a paper originally published on April 15, 2005,  retracted their article stating:

• "Upon  review of the data published in this article, the authors have been  unable to reproduce some of the reported spontaneous transformation  events and suspect the phenomenon is due to a cross-contamination  artifact."[5]

The paper, titled "Spontaneous Human Adult Stem Cell Transformation" [6],  included research on human stem cells which were reported to  "transform" into cancer-like cells.  The 2005 paper was cited many times  by other researchers who, like the authors, were astounded at the  possibility that stem cells could be "cancer-like".  The contamination  was later found to be due to HT1080 cells, a cancer cell line that  overgrew the stem cell culture.

Absolutely!   We currently accept samples from around the world, including, but not  limited to England, Australia, Italy, Singapore, India, Hong Kong,  Canada, Argentina, Mexico, Norway, The Netherlands, Scotland, South  Africa, Spain, Chile, and Malaysia.  The best option for sending samples  overseas is to extract and quantitate the DNA from your cell line  sample(s) in your own laboratory (or send a DRIED cell pellet).  The  extracted DNA or dried cell pellet from your cell line samples do NOT  need to be on ice; shipping at ambient temperature is sufficient and  causes no problems with the cell line authentication testing process.   Sending a bulky dry ice package internationally could be expensive and  potential shipping delays could damage the samples.  If you prefer to  send fresh/frozen cell pellets - please contact us for the best option  for your specific needs.   

If  a mixture of more than one human or mouse cell line is present there  will be more than two peaks at several loci in your STR DNA profile  report/data.  The peak height value is indicative of the signal strength  of that allele, which theoretically should have a direct relationship  to the amount of DNA in the sample.  Hence, in a mixture of human or  mouse cell lines where some of the peaks at a locus are significantly  higher than others, the larger peaks would belong to the cell line that  was the major component of the mixture.  The smaller peaks would then  belong to the minor component of the mixture. 

Please  be aware that a mixture of two or more cell lines can look very similar  to "genetic instability" in a cell line - where subpopulations of the  genuine cell line exist which have a different STR DNA profile at some  genetic loci due to genetic instability which is inherent to cancer cell  lines.  It is therefore crucial that a trained DNA analyst helps to  interpret the electropherogram (peak) data in these difficult cases to  eliminate a possibility of a mixture as the cause of the additional  alleles.  We are always here to help, so don't hesitate to contact us if  you have questions about your data.​​

 Yes!  The International Cell Line Authentication Committee (ICLAC) maintains  an up-to-date list of all human cell lines that are known to be  misidentified.  Check your cell lines today to see if they are on this  list - see link below. 

ICLAC Register of Misidentified Cell Lines

Visit our "Journal & NIH Guidelines" page for more information. 

 We  have validated a mouse cell line authentication test which is now  available to our clients.  Both human and mouse cell line and sample authentication is  done via STR profiling.

Visit our Mouse STR Profiling Page Here 

The data you receive from Labcorp can be used to compare your submitted  sample's STR profile to the STR profile of the reference cell line  sample (either a repository cell line or patient sample, if a reference  STR profile is available).  All of the STR DNA loci that we tested are  used in the repository reference STR databases so you will be able to  compare the STR profile from our test with any of those databases.  If  you purchased your cell line from a repository, then the reference  profile will be available through their website.

If the STR DNA profile of your submitted cell line matches the known  reference cell line's STR DNA profile at every overlapping genetic site,  then your submitted cell line is "authenticated".  If there are  differences present, it could mean misidentification, mislabeling,  contamination by another cell line or genetic instability.  For human  cell lines a percent match of 80% or above is considered "authenticated" [4],  anything below that threshold should be regarded with suspicion (please  note that the statistical approach to mouse cell line authentication is  under evaluation in the scientific community).  If the tested cell line  has been contaminated or misidentified, additional authentication  testing should be done on earlier passages of that cell line to identify  where the problem originated, or a new cell line stock should be  obtained from a reputable source.  Any research experiments done with a  contaminated or misidentified cell line may have to be performed again  with a genuine stock before publishing or moving forward with your  research. 

Still  having trouble with your results? We are here to help!  Contact your cell line testing representative and ask as many questions as you need  to.

We are listed as a service provider for cell line authentication testing on  several different websites, including the American Association for Cancer Research (AACR) website.  We have been in the human DNA  identification business for over 30 years and the lab has the  accreditations and technical experience to support these services at the  highest level.  

Many of our clients have already published in various  reputable journals using our cell line authentication testing results -  ask us for references for journal articles that include our results and testing! 

 All of our report options offer the same high quality STR profiling test  (we use PowerPlex 16HS for human STR (includes a mouse marker) and we  test (18) mouse specific loci plus two human markers for mouse cell line  authentication), the difference and what determines the price is the report format.   Please note, the electropherogram (peak) data, included with each  test, is a useful tool for monitoring your cell line's identity,  especially when you have your cell line tested for authentication as the  passage number increases over time.

Option #1 is our most cost efficient option and is perfect for routine quality  control testing of your human or mouse cell line or other  tissues/samples.  

What you get:

• Excel spreadsheet of the ANALYZED STR DNA profiles of all cell lines submitted in one batch 
• Peak data for EACH submitted specimen
  

Option #2 is  our first "report" option signed by a Laboratory Director.  This option  is typically selected when a formal signed report is needed for EACH  cell line but when the researcher needs a more cost efficient report  versus Option #3 or #4.

What you get:

• Analyzed  STR DNA profile of your submitted cell line in a formal signed report  (no reference profile comparison) - each submitted sample will have an  individual report
•  Peak data for EACH submitted specimen
  

Option #3 is the most comprehensive "report" option that we offer and it is signed by a Laboratory Director. 

What you get:

• Formal  signed report that includes analyzed STR DNA profile of your submitted  cell line side-by-side with the KNOWN reference STR profile for that  cell line, if available (e.g. from ATCC, Cellosaurus, etc)
• Comprehensive  interpretation that includes percent match and percent identity  calculations which indicate how closely your submitted cell line matches  the known reference cell line
• Peak data for EACH submitted specimen
  

This report will clearly indicate if your cell line is authenticated,  misidentified, or "unique" among repository reference STR profiles.

​Option #4 is a "report" option signed by a Laboratory Director. This option is used  most often for researchers who submit two specimens for comparison to  EACH OTHER; it is useful for labs creating in-house cell lines (e.g.,  compare patient sample to low passage stock of established primary,  cancer or stem cell line) or when testing xenografts from patient  tissue.
What you get:

• Formal  signed report that includes the analyzed STR DNA profile of your  submitted "questioned" specimen side-by-side with the analyzed STR DNA  profile of the submitted "reference" specimen
• Comprehensive  interpretation that includes percent match and percent identity  calculations which indicate how closely your submitted specimen matches  the submitted reference specimen  
• Peak data​ for BOTH specimens