"An authentic cell line is a cell line of a specific species that retains its unique functionality and characteristics. Cell line authentication is a set of tests intended to demonstrate that a cell line is what it is reported to be. Short Tandem Repeat (STR) Profiling is a form of interspecies cell line authentication that looks for the variation of tandem repetitive sequences in your cell line. STR profiling is rapid, reproducible, and uses a standardized PCR-based method for the authentication of human cell lines" –From ATCC
Please dilute extracted cell DNA samples in low TE buffer (only with 0.1 mm EDTA) as too much EDTA is inhibitory to PCR. If possible, elute the DNA sample with low TE buffer during DNA extraction and please contact the technical support of the company of your DNA extraction kit to confirm the feasibility.
Please put the DNA concentration, concentration measurement method, such as Nanodrop, Qubit, etc., and 260/280 ratio (if known, and this information is important for us to determine your samples’ quality) in the order form.
Sample ID should be no more than 8 letter/number. Letter and number only and no blank or special characters. Sample ID in you order form must match the ID on the top of the sample tub.
Minimum volume of each genomic DNA sample: 20uL
Required concentration: 10ng/ul
Samples can be shipped at ambient temperature.
To determine whether the test cells are related to the reference cells in the STR database, enter the STR marker information we provide in the report to https://atcc.org/en/STR_Database.aspx (registration required)
For detail, please read "View our brief tutorial before starting."
As shown below, Information on the STR markers of your cells can be found in the allele 1, 2, or 3 columns in the report sent to you.
The ATCC website will automatically provide the percent match of your test cell lines with the reference cell line in the database. However, we recommend that you calculate it manually to double check, as the result provided by the ATCC database is not always correct. Please check "how to calculate percent match" below for more details.
The percent match determines whether cell lines are related or not. Cell lines matching at no less than 80% of alleles across 8 major loci are considered to be related and can be authenticated. Although there are several methods to calculate the percent match, the life technology scientist recommends using the method shown in ASN-0002: Authentication of Human Cell Lines: Standardization of STR Profiling.
Percent Match= The number of SHARED ALLELES of two cell lines X (%) / The total number of alleles in questioned profile (test cells line)
The percent match is based on comparing only the 8 core STR markers (marked in Blue in table 1) plus amelogenin (highlighted in yellow in table 1) of the questioned profile (test cell lines) with those markers in reference cell lines in the database.
The following table, table 1, shows how to calculate percent match.
question( test) cell line
As shown above, there are 13 shared alleles (in red) between the questioned profile (test cell line) and the reference cell lines in the database. There are 14 alleles in total in the questioned cell lines. Therefore, the percent match of the test cell line and the reference cell line, U-87, is 92.8 %. Please note that the homozygous allele is counted as one allele. To protect the privacy of the cell donor, the database only provides 8 core STR markers plus amelogenin and does not provide information for the rest of 7 STR markers, which were shown in our report. However, the information from these 8 core STR markers are enough to authenticate a cell line for research and publication purposes. The information for the rest of SRT markers only serves as internal reference.
There are several ways you may send your samples to the Core.
If you are from Northwestern and are on the Chicago campus, you can bring your samples directly to the facility's lab location. Fresh samples brought directly to the Core should be stored in the DNA Extraction room refrigerator. Please drop off samples directly to a technician at the Core if they need to be stored at -80°C.
If you are from Northwestern and are on the Evanston campus, you can drop your samples off at one of the two courier locations in the Hogan Building, 2205 Tech Drive: Hogan 2-100, BMBCB administrative office, or Hogan 4-150. The couriers pick up the samples every morning and we receive them in the afternoon.
If you are not on the Northwestern campus, please send your samples through an independent carrier such as FedEdx or UPS to the address listed under Contact Us. Prior to shipping, please contact a technician to schedule delivery. At the time of shipping, please send an email notification with your express mail tracking number. This will allow us to watch for your shipment. We prefer that samples are sent overnight on Monday or Tuesday so that we can guarantee someone is here to accept them. We will notify you when your shipment is received.