DEC 14, 2020 2:00 PM PST

STR Genotyping for Human Sample Identification

SPONSORED BY: Promega Corporation

Human sample identification is an essential element of many research projects employing human cells, tissues, or mixtures. Identification may be required to track and confirm sample provenance for databasing, biobanking, or research purposes. For example, archival tumor/normal specimen pairs may be tested to confirm they are derived from the same individual. Human identification may also be used as verification of twin zygosity or parentage in research studies to improve reliability of familial information. In its most sensitive application, human identification may be used to detect mixtures in human research samples—to rule out external contamination in samples, to identify contamination due to histological procedures, to track chimerism, or to study xenografts, among other things.

DNA genotyping using short tandem repeat (STR) markers is currently the gold-standard for human sample identification. STR markers consist of short, repetitive sequence elements 3–7bp in length. Distributed widely throughout the human genome, STR markers are highly polymorphic genetic markers which may be used for both forensic and non-forensic human identification. Genotyping at STR markers can be performed using PCR with dye-labeled primers. The number of repeats for each allele in a given individual can be determined, based on the size of the amplified fragments, following electrophoretic separation on a capillary electrophoresis instrument.

There are fluorescent PCR multiplex STR kits optimized for human sample identification in research labs. These kits include several highly polymorphic STR markers plus two sex-linked markers. Lab workflows can be streamlined when all markers can be amplified in a single PCR reaction. A high number of markers allows for better discrimination between human samples, including related individuals. Used in detection of human mixtures, this system also increases the likelihood of informative alleles, unique to both contributors, that can be used to estimate their relative contributions to the sample. 

While many researchers have relied on forensic chemistries that are often intended for samples with very low DNA concentration, kits that have been optimized for 2.5–5ng DNA input specifically for the research community are desirable. The increased DNA input can improve robust detection of minor genetic contributors by reducing stochastic effects on PCR. 

The availability of benchtop capillary electrophoresis instruments paired with multiplex STR kits brings the capability of human sample identification to individual labs. The small footprint and low-to medium throughput of these instruments means that research labs can now perform their own testing without waiting for sample batching or core lab turnaround. Researchers can control the entire workflow, from amplification and electrophoresis conditions, to data analysis, with a potential for faster turnaround to support key research projects. 

Human sample identification and mixed sample analysis with STR genotyping can confirm sample provenance and identify sample contamination or chimerism in many research areas, even the most sensitive applications. To learn more about DNA genotyping using STR markers with the Spectrum Compact CE System for detection of low-level human contributors in mixed samples, download the application note: Human Sample Identification and Mixed Sample Analysis Using the GenePrint® 24 System

About the Sponsor
  • With a portfolio of more than 4,000 products covering the fields of genomics, protein analysis and expression, cellular analysis, drug discovery and genetic identity, Promega is a global leader in providing innovative solutions and technical support to life scientists in academic, industrial and government settings.
You May Also Like
NOV 26, 2020
Clinical & Molecular DX
Routine Diagnostic Tests Linked to a 59 Percent Increase in Testicular Cancer Risk
NOV 26, 2020
Routine Diagnostic Tests Linked to a 59 Percent Increase in Testicular Cancer Risk
New research has revealed that exposure to radiation from diagnostic procedures such as X-rays could contribute to an el ...
JAN 07, 2021
Cardiology
Climbing Some Stairs is a Good Way to Check Heart Health
JAN 07, 2021
Climbing Some Stairs is a Good Way to Check Heart Health
If you can climb four flights in under a minute, your heart is probably in good shape, according to new work presented a ...
FEB 03, 2021
Clinical & Molecular DX
New Panel of Arthritis Biomarkers Diagnoses Disease With 93.2% Accuracy
FEB 03, 2021
New Panel of Arthritis Biomarkers Diagnoses Disease With 93.2% Accuracy
Rheumatoid arthritis, or RA, is a painful and debilitating autoimmune disorder of the joints, particularly those of the ...
FEB 17, 2021
Clinical & Molecular DX
Urine Test Bypasses the Need for Prostate Biopsies
FEB 17, 2021
Urine Test Bypasses the Need for Prostate Biopsies
Researchers have created a urine test for prostate cancer that could make unnecessary biopsies a thing of the past. The ...
MAR 09, 2021
Clinical & Molecular DX
AI Creates Space for Equality in Pain Management
MAR 09, 2021
AI Creates Space for Equality in Pain Management
Pain is experienced more intensely among certain groups of people. Indeed, studies have shown that individuals from mino ...
MAR 09, 2021
Cardiology
A Lifestyle Change Could Reduce a Diabetic's Cardiovascular Risk
MAR 09, 2021
A Lifestyle Change Could Reduce a Diabetic's Cardiovascular Risk
Nowadays, everyone thinks there is a pill or gummy that will fix everything. That may be true for the occasional headach ...
Loading Comments...