CHIDB - Performance: Chimerism-Donor

Test Catalog

Test Name

Test ID: CHIDB    

Method Description Describes how the test is performed and provides a method-specific reference

Genomic DNA is extracted from blood or bone marrow aspirate samples using an automated extraction machine (EZ1 BioRobot, Qiagen) and used in a commercial kit  GlobalFiler PCR Amplification KIT (Applied Biosystems, Foster City, CA) following the manufacturer's instructions. Briefly, 20 different short tandem repeat (STR) marker regions are amplified in single multiplex PCR using primers labeled with fluorescent tags. The products are analyzed for size and amount using capillary electrophoresis on an ABI3500xl genetic analyzer. For the initial sample on any patient, the test is performed on 3 separate DNA samples: donor germline DNA, recipient germline DNA, and recipient posttransplant sample for chimerism determination. The STR profile of the germline samples is used to identify markers that can distinguish between the donor and recipient. Based on these profiles, the percentage of donor and recipient DNA is then determined in the posttransplant sample using the assumptions and calculations outlined in Thiede C et al 1999. Subsequent samples for chimerism evaluation do not need to be accompanied by samples for donor and recipient germline evaluation, as the profiles from the initial testing are kept on file for comparison.


The sensitivity of this analysis is approximately 5% in a posttransplant specimen (donor and recipient DNA mixed chimerism).(EZ1 BioRobot System. User Manual July 2005. Qiagen.; GlobalFiler PCR Amplification Kit. User Bulletin 2004. Applied Biosystems, Foster City, CA.;Thiede C, Florek M, Bornhauser M, et al: Rapid quantification of mixed chimerism using multiplex amplification of short tandem repeat markers and fluorescence detection. Bone Marrow Transplant 1999;23:1055-1060)

PDF Report Indicates whether the report includes an additional document with charts, images or other enriched information


Day(s) and Time(s) Test Performed Outlines the days and times the test is performed. This field reflects the day and time the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time required before the test is performed. Some tests are listed as continuously performed, which means assays are performed several times during the day.

Monday through Friday; 9 a.m.

Analytic Time Defines the amount of time it takes the laboratory to setup and perform the test. This is defined in number of days. The shortest interval of time expressed is "same day/1 day," which means the results may be available the same day that the sample is received in the testing laboratory. One day means results are available 1 day after the sample is received in the laboratory.

4 days

Maximum Laboratory Time Defines the maximum time from specimen receipt at Mayo Medical Laboratories until the release of the test result

8 days

Specimen Retention Time Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded

3 months

Performing Laboratory Location The location of the laboratory that performs the test