I'm always fascinated to learn more about how our customers use our products. What diseases are they studying? What geographic areas are they targeting? What are they hoping to achieve? It's these questions and more that make every day interesting at DNA Genotek. I recently had the privilege to learn more about how one of our customers is using our product and I wanted to share that knowledge with you.
The South African Tuberculosis Vaccine Initiative (SATVI) of the University of Cape Town is a new customer who has tried the Oragene•DNA Self Collection Kits for the first time. SATVI's aim is to develop novel tuberculosis vaccination strategies. Their focus is on the clinical side of tuberculosis vaccine development. They therefore embark on clinical, epidemiological, immunological and genetic research to answer critical questions in TB vaccinology.
A large focus of SATVI's research is aimed at identifying host correlates of protection against TB, following BCG vaccination. These studies include looking at genetic differences between infants who are either protected or not protected against TB, following BCG vaccination. They are also interested in determining if there is a genetic disposition to susceptibility to TB by recruiting parents of both the protected and unprotected infants. They are collecting DNA from both infants and their parents, and will conduct target gene and whole genome screening to delineate polymorphisms that associate with protection. Over the course of the 4 year study, approximately 6000 samples will be collected.
SATVI's project is not without its challenges. Maximizing compliance of potential study participants is a major challenge faced by the SATVI researchers. In order to maximize the number of study participants, the researchers identify potential participants through procedures in place either at clinics or home visits. Subsequently, an appointment is scheduled with the whole family where the DNA samples are collected for isolation.
The study was begun with blood collection for DNA isolation of the participants. However, the researchers encountered misbleeds and study withdrawals from some participants, mostly because of concerns or fear of blood collection methods. A large percentage of the potential study participants are children so the researchers felt a non-invasive method of DNA collection would be very beneficial.
Recently the SATVI researchers decided to use Oragene•DNA for the sample collection because it offered them a non-invasive, easy to use and reliable method to collect samples. In addition, the Oragene•DNA kits were cheaper, less invasive and thus more appropriate for collecting from both children and adults in clinic environments and home settings.
The researchers were able to achieve an outstanding 95% compliance rate with the non-invasive saliva collection method available with the Oragene•DNA kits. Overall, participant drop out has been reduced with the non-invasive collection process. In addition, they are achieving very high quantity of DNA with an average of 200ng/ul of DNA from adult saliva and 90ng/ul from infants. The quality is also very high with an A260/280 of 1.7-1.9. Oragene•DNA has performed reliably on their downstream processes - generating equivalent results to the blood kits used previously.
Overall, the use of Oragene•DNA kits has resulted in cost savings. The Oragene•DNA kits were less expensive than the isolation kits used to isolate DNA from blood. SATVI was also able to eliminate the cost of re-collecting blood for phlebotomies that failed on the first attempt.
"We believe the Oragene•DNA system is the most practical for collecting DNA in this environment. The Oragene•DNA kits are cheaper, less invasive and thus more appropriate in our setting," said Muki S. Shey, PhD Student, South African TB Vaccine Initiative (SATVI), Institute of Infectious Disease & Molecular Medicine (IIDMM), University of Cape Town. "Donors who have provided blood samples for other studies and who have now used the Oragene•DNA kits say they much prefer the non-invasive method of collection with Oragene. We would definitely recommend the kit to anyone who wants an easy and reliable method of collecting samples for DNA isolation."
SATVI's successful use of Oragene•DNA to study TB opens up a new opportunity for all infectious diseases researchers who would traditionally rely on blood collection methods.
Did this article interest you? Leave a comment and let us know what you think.
Photo credit: (top photo) Muki Shey, second photo (Fabio Julies).
If you've been following our blog or our newsletter, you're probably aware that DNA Genotek has experienced significant growth in our partner program. We've added partners across all categories: genomics service providers, diagnostic service providers and technology vendors.
One of the newest partners to complete this validation process is Precision Biomarker Resources. Precision Biomarker provides automated, high-throughput microarray services to expedite the biologic investigations of pharmaceutical, biotechnology and academic researchers. Their services include: nucleic acid isolation, SNP genotyping, expression profiling, qPCR protocol design and processing, and custom bioinformatic analysis. Precision Biomarker Resources serves as a Genomics Service Provider for investigators working with DNA Genotek’s Oragene•DNA sample collection system.
Precison Biomarker is also the first partner to provide a special offer to Oragene•DNA customers to help them celebrate their successful completion of the partner program requirements. I'm pleased to share this news with you and pass along information about this limited time promotion.
From now until September 30th, 2010, Precision Biomarker Resources will include free DNA isolation from your Oragene•DNA samples as part of any whole genome genotyping project performed by Precision Biomarker Resources and using the Affymetrix SNP Array 5.0 or SNP Array 6.0 microarrays. A minimum of 30 samples must be submitted to qualify. Samples and a purchase order for the accompanying genotyping service must be received by Precision Biomarker Resources before September 30th, 2010.
To schedule your experiment now, please call Precision Biomarker toll free 888-857-0752 or e-mail sales@precisionbiomarker.com. Be sure to include your name, institution and contact information (phone number and e-mail) so that they can contact you if we need any additional information.
What do you think of DNA partners offering special incentives for Oragene•DNA customers? Would you like to see more offers like this? If so, leave a comment and let us know.
Photo credit: Alexandra Simms
We were recently introduced to an organization at the heart of a movement focused on the fight against HIV/AIDS, tuberculosis and malaria. It’s a movement that is designed to end these diseases faster.
The organization is called the Global Business Coalition (GBC) on HIV/AIDS, tuberculosis and malaria and DNA Genotek has joined the GBC in its fight to end these diseases. DNA Genotek chose to join the GBC because there is a natural fit between their mandate and our technologies. GBC brings together businesses across various sectors to help fight global epidemics. Our products, designed to enable safe, easy and reliable collection of DNA and RNA samples, are the building blocks to genetic research and analysis of these diseases. The Oragene family of products is unique in that they facilitate research in low-resource settings where these diseases are most prevalent.
John Tedstrom, GBC’s president and CEO commented on DNA Genotek’s involvement: “DNA Genotek, with its expertise as a leader in enabling genetic research, will be a powerful asset to the Coalition. It is by connecting the technical expertise of companies like DNA Genotek with our partners in government, civil society and the multilateral community that we’ll be able to defeat these diseases faster.”
Ian Curry, president and CEO of DNA Genotek commented: “Understanding the genetic basis of HIV/AIDS, TB and malaria is critical to discovering new prevention and treatment options. DNA Genotek’s Oragene•DNA family of products has facilitated the genetic study of many diseases. It is our hope that our work with the GBC will enable research that may one day lead to the identification of the genes involved in these diseases or genes which cause resistance to treatment so that effective measures can be taken.”
Our involvement in the GBC allows us to continue to pursue our goal of enabling worldwide health improvements. We are all looking forward to working with the GBC.
What do you think of initiatives like this? Leave a comment and tell us your thoughts.
Beckman Coulter Genomics has developed a new version of their DNAdvance System specifically for use with DNA Genotek’s Oragene•DNA samples.
DNAdvance SP, from Beckman Coulter Genomics, is an extraction kit for the isolation and purification of DNA from saliva samples collected with Oragene•DNA Self Collection Kits. The high throughput genomic DNA (gDNA) isolation reagent system enables the purification of high quality DNA from saliva samples, making it ideal for genotyping applications (SNP, fragment analysis), sequencing and qPCR. The system provides researchers and laboratories with an optimized and robust solution for DNA extraction and purification from saliva collected with Oragene•DNA kits.
Bassam El-Fahmawi, product manager, strategic marketing with Beckman Coulter Genomics stated: “We chose to develop DNAdvance SP for Oragene•DNA samples because more and more of our customers are using this proven, non-invasive collection method. Customers will see the benefits of our collaboration in the consistent, high quality results delivered by the system.”
Cindy Maccullough, vice president marketing at DNA Genotek commented: “The development of the DNAdvance SP System is a clear sign of the growing interest in non-invasive DNA sample collection in the scientific community. There is an increasing demand for automated extractions from our customer base, and the DNAdvance SP System provides a streamlined extraction process that delivers predictable, quality yields for Oragene•DNA.”
The DNAdvance SP product is available from Beckman Coulter Genomics. For more information, you can contact Beckman Coulter here.
The Genetic Link welcomes guest blog authors. This guest submission is from Megan P. Hitchins, PhD. Medical Epigenetics Laboratory, Lowy Cancer Research Centre, University of New South Wales, Sydney, Australia. We thank Dr. Hitchins for her submission and welcome her as a guest author. I hope you enjoy this article.
A host of familial cancer syndromes have been described in which several members of the same family develop cancer at a young age due to an inherited genetic susceptibility. It has been well established that germline mutations in the DNA sequence of genes that are protective against cancer, including tumour suppressor and DNA repair genes, are the culprit in most familial cases of cancer. Because they are inherited, these germline mutations are present in every cell of the body from conception into adulthood, knocking out one of the two copies of the protective gene. They confer a high risk of cancer development at a young age, although the cancer itself arises when the remaining normally-functioning copy of the gene is knocked out in susceptible tissues due to contributing environmental conditions, taking with it the last remnants of protection it once afforded against cancer. However, for a number of individuals with young-onset cancer, as well as entire families, the inherited defect remains unidentified, which complicates genetic counselling and clinical management of family members. Lynch syndrome is the most common of all family cancer syndromes, in which patients develop a range of cancers, the most frequent of which are colorectal and uterine cancers. Lynch syndrome is usually caused by germline mutations within one of the four genes that encode the mismatch repair system, most commonly MLH1 or MSH2. Loss of protection from the mismatch repair system results in the accumulation of mutations during cell division, and ultimately, cancer ensues. However, in about a third of Lynch syndrome patients, standard genetic screening fails to identify any pathogenic sequence change within the mismatch repair genes that might be responsible for their disease.
The focus of the Medical Epigenetics Laboratory at the Lowy Cancer Research Centre in Sydney, Australia, led by Megan Hitchins PhD, is to determine the role of a new type of defect, termed a "constitutional epimutation" in predisposing to young-onset cancer syndromes. The first case of a "constitutional epimutation" was reported for the MLH1 gene in a patient with Lynch syndrome in 2002.1 This represents a new epigenetic mechanism of cancer susceptibility, in which the gene's promoter (the equivalent of its engine) is clogged with the chemical methylation, causing the affected copy to be switched off, even though its DNA code is entirely normal. Thus, "epimutation" refers to the nature of the defect, which occurs over and above the context of DNA sequence, whilst "constitutional" denotes the intrinsic presence of this epigenetic defect in normal tissues. Cancer similarly develops after the active copy of the gene is lost in the vulnerable tissues, giving rise to the same clinical profile as carriers of conventional sequence mutations of MLH1. However, one of the key differences between a constitutional epimutation and a sequence mutation is that the gene methylation can be unstable and sometimes show a "mosaic" pattern, that is, it may be present in a patchwork of some cell or tissue-types, whilst absent in others. The level of methylation in the body may even vary during the course of the carrier's life-time. This facet of epimutations adds to the challenge of identifying those who carry them, since their identifying factor - the presence of methylation - may not necessarily be detectable in DNA extracted from a single source, typically peripheral blood. A further complicating factor is that unlike germline mutations that demonstrate classic Mendelian patterns of inheritance, transmission of epimutations from one generation to the next is unpredictable. This non-Mendelian inheritance is attributable to the fact that methylation is stripped away during the reproductive life-cycle, and so epimutations tend to be reversed between generations and may, or may not, be re-imposed after fertilization in the developing fetus. Indeed, it is likely that the degree of methylation mosaicism witnessed in carriers reflects the stage of embryogenesis during which the methylation was established in them. Therefore, when it comes to screening for epimutations, for instance in the family members of a cancer patient found to carry one, it is prudent to test the DNA extracted from more than one tissue-type. Otherwise, it begs the question of whether a negative test means those relatives are safe from cancer as non-carriers, or whether it is just didn't show up in the tissue tested due to the mosaic nature of methylation. To minimise the possibility of failing to detect an epimutation, we have adopted the approach of testing DNA extracted from different tissue sources, namely blood, hair bulbs, buccal swabs, and thanks to the Oragene kits, saliva. In fact, since saliva is originally derived from the same embryonic cell lineage as the colon, it may even provide a more accurate representation of the epigenetic changes that have occurred in the colon than blood. In our recent article in the International Journal of Cancer,2 we show for the first time that in one case, Patient YT, who developed colon cancer at the age of just 18 years due to a constitutional MLH1 epimutation, that methylation was present in his saliva, as per other normal cells (Figure 1a). Thus his saliva showed a consistent pattern with other sources of tissue, indicating a severe soma-wide epimutation (Figure b). Furthermore, using the saliva RNA extraction kit, we were also able to show that the methylated copy of the gene was completely switched off (Figure 1c). Interestingly, screening of his parents showed that neither of them had any detectable methylation, despite screening multiple tissues including their saliva, and so we could say with confidence that the epimutation had arisen spontaneously in their cancer-affected son, but that they themselves were not at an elevated risk of developing cancer from the same type of defect.
Figure 1. Constitutional MLH1 epimutation in "Patient YT"
A: Schematic overview comparing a constitutional epimutation of MLH1, as found in Patient YT, with the normal gene of a healthy individual. Rectangles denote the two copies of the gene and its mRNA product. Methylation of the promoter is depicted by black lollipops. Gene activity is denoted by a waved arrow. The common c.655A>G SNP within the protein-code portion of the MLH1 gene is shown, which enables the two copies of the gene to be distinguished from one another, allowing the activity of the two alleles to be traced in the mRNA. B: Allelic patterns of MLH1 methylation showed methylation was widespread in normal somatic tissues, including saliva collected using the Oragene kit. The "beads of string" represent individual strands of DNA from the MLH1 promoter with dots showing positions of methylation present (black) or absent (white) at CG sites within the DNA sequence, at which methylation is capable of binding. C: Quantification by pyrosequencing of the two copies of the MLH1 gene in the genomic DNA and mRNA samples derived from saliva collected using the Oragene kits. The yellow-shaded region shows the peaks representing each allele at the SNP site. Two peaks showing equal levels of the ‘A' and ‘G' alleles in his saliva DNA show the patient is heterozygous for the benign c.655A>G SNP, allowing the two copies of to be differentiated. However, in his saliva mRNA, only the ‘G' allele was detected, indicating that the ‘A' allele has been switched off by the promoter methylation further upstream.
Our laboratory now routinely collects saliva using the Oragene kits from patients with colon cancer who we suspect may have been caused by intrinsic epigenetic changes, since we believe methylation may be elevated and hence more easily detected in this source of DNA than in blood. Furthermore, we are finding that our rate of compliance in providing samples for diagnostic or research purposes has increased. Firstly, those who are elderly, sick or have an aversion to needles are more willing to provide a sample of saliva than blood for DNA or RNA extraction. Secondly, in our research endeavouring to unravel the inheritance pattern of constitutional MLH1 epimutations, we rely on the voluntary contribution of specimens from the asymptomatic relatives of cancer patients who carry this defect. Relatives are happier to provide a specimen of saliva at their own convenience and in the comfort of their own home, than in visiting their clinician or pathology laboratory to provide a blood sample. Following contact by phone with the genetic counsellor or research nurse, they simply place their saliva sample in the stamped addressed envelope we provide and return it to the laboratory by post, along with their signed consent form approving the inclusion of their sample in our research study. To this end, the Oragene saliva kits have greatly facilitated our research from a logistical perspective, whilst also providing a new dimension for testing different tissue-types for epigenetic changes that may vary from one tissue source to another.
References.
- 1. Gazzoli, I., Loda, M., Garber, J., Syngal, S. & Kolodner, R.D. A hereditary nonpolyposis colorectal carcinoma case associated with hypermethylation of the MLH1 gene in normal tissue and loss of heterozygosity of the unmethylated allele in the resulting microsatellite instability-high tumor. Cancer Res 62, 3925-8 (2002).
- 2. Goel A, Nguyen T-P, Hon-Chiu E Leung H-CE, Nagasaka T, Rhees J, Hotchkiss E, Arnold M, Banerji P, Koi M, Kwok C-T, Packham D, Lipton L, Boland CR, Ward RL, Hitchins MP. De novo constitutional MLH1 epimutations confer early-onset colorectal cancer in two new sporadic Lynch syndrome cases, with derivation of the epimutation on the paternal allele in one. International Journal of Cancer 2010, in press.
A few weeks ago, I posted an article about best practices for long term storage of unpurified Oragene•DNA samples on The Genetic Link. The response to the article was positive so I'm following up with today's story about long term storage of DNA purified from Oragene•DNA samples.
The preservation and storage of DNA is an important consideration for molecular epidemiology and population studies. As the makers of the Oragene•DNA family of products, we have prepared these recommendations for the long-term storage of DNA purified from saliva samples collected with Oragene•DNA to help our customers achieve optimal results.
Preventing DNA Degradation
There are three major causes of DNA degradation in a purified sample (ref. 1). Samples may be accidentally contaminated by bacteria, but storage at 4°C or lower will minimize bacterial metabolism and the release of nucleases. DNases may be inadvertently introduced from the skin, but this can be minimized by wearing gloves when handling samples. Repeated cycles of freezing and thawing may also contribute to DNA degradation. This may be minimized by splitting the purified DNA into multiple aliquots and thawing one at a time.
There are two major causes of degradation of purified DNA:
- Acid hydrolysis - due to storage in a solution with no buffering capacity, explained in "Comparison of TE and water" section
- Nuclease activity - DNases may come from the skin of the person handling the sample, contaminated labware or bacterial contamination of the purified sample. Use of gloves can minimize contamination from the person and use of nuclease-free labware and working in a clean environment can prevent both nuclease and bacterial contamination. Additionally, inclusion of a metal ion-chelating agent, such as EDTA, in the storage buffer can effectively inhibit the activity of any DNases present in the sample.
Comparison of TE and water
Kasper and Lenz (ref. 2) performed an 8-year study of DNA stored in water or Buffer AE (10 mM TrisHCl; 0.5 mM EDTA, pH 9.0). DNA stored in Buffer AE at -20°C or 2-8°C showed no degradation by gel electrophoresis and amplified well in a PCR assay. DNA in water remained intact when stored at -20°C but samples were degraded when stored at 2-8°C and performed poorly in a PCR assay. Pure water lacks buffering capacity and an acidic pH may lead to DNA hydrolysis.
Biobank recommendations
An EU workshop on Biobanks (ref. 3) recommends freezing DNA samples to prevent bacterial contamination and to minimize evaporation of the sample. Tris-EDTA (TE) buffer contains sufficient buffering capacity to prevent acid hydrolysis of DNA. Similarly, the UK Biobank (ref. 4) recommends the storage of DNA in a nuclease-inhibiting environment at a temperature of -20°C, since no significant increase in stability is observed at temperatures below -20°C.
References
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O'Brien, D. (2002). High-throughput DNA purification. Modern Drug Discovery. 5(3), 25-26.
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Kasper, Y. et Lenz, C. (2004). Stable 8-year storage of DNA purified with the QIAamp DNA Blood Mini Kit. QIAGEN News. 2004 e10.
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Biobanks for health: Optimising the use of European biobanks and health registries for research relevant to public health and combating disease. Report and recommendations from an EU workshop held at Voksenåsen Hotel, Oslo. January 28-31, 2003.
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Sample handling and storage: Subgroup protocol and recommendations. Version 1.0. UK Biobank. July 7, 2004
We hope these best practices will help you optimize the long term storage of all your purified Oragene•DNA samples. If you like this article, be sure to let us know by leaving a comment.
The number of clinical trial and epidemiological studies collecting genomic DNA from a large number of individuals is increasing rapidly. There are many options for obtaining these biospecimens including blood collection, saliva collection, tissue and more. Yet, recruitment is perhaps the most challenging part of any scientific research study. Potential study participants are often reluctant to participate because they are needle phobic, do not want to travel to a specific location to participate in the collection process or are otherwise inconvenienced by the study criteria. Problems with recruitment can disrupt the timetable for a research project, preoccupy staff and, ultimately, result in a trial being abandoned (Ashery & McAuliffe, 1992).
At DNA Genotek, we set out to discover how several successful studies have been able to meet their recruitment and compliance goals in a timely way and to summarize their success criteria in a report. We accomplished this through telephone interviews and by reviewing published research. Many of your peers provided the kind of insight that previously had not existed. The result of this work is the research report titled: Overcoming challenges in DNA sample collection - How epidemiological researchers are maximizing compliance rates with non-invasive DNA self-collection.
This report will help you discover:
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How successful researchers are achieving dramatically higher compliance rates (70.52% to 95% in the first phase of collection)
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What processes (from qualifying participants to analyzing results) most contribute to higher compliance rates
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Whether centralized or mail-based collection impacts compliance rates
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How to overcome challenges to maximize compliance
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How to take a good compliance rate and make it an outstanding compliance rate
- What issues most affect compliance rates
If you're considering starting a clinical trial or epidemiological study, it's our hope that this report will help you build the criteria for successful DNA collection and for maximizing your compliance rate. If you're already working on a study, feel free to examine what these experienced researchers are doing (and use this study to help others).
Want to learn more about how to meet your recruitment and compliance goals?
Download this free report to learn best practices for recruitment and compliance from top research organizations.
Would you like to see us publish more reports like this? Leave a comment and let us know.
This month, PLoS ONE published a new research study that I think will interest readers of The Genetic Link. The study, titled "Array-Based Whole-Genome Survey of Dog Saliva DNA Yields High Quality SNP Data", was written by Jennifer S. Yokoyama, Carolyn A. Erdman and Steven P. Hamilton of the Department of Psychiatry and Institute for Human Genetics, at the University of California, San Francisco. The study is interesting for several reasons.
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The study highlights the availability of array-based genotyping platforms for canines but notes that they require large quantities of high quality genomic DNA.
- The authors state that there is an increasing demand in the research and clinical communities for larger sample studies to ensure statistical significance.
- The study notes that DNA sampling can become the limiting factor when studying canine behavioural traits.
The authors evaluate the performance of whole blood and Oragene•ANIMAL DNA collection kits for GWAS studies. DNA from all samples was analyzed using Illumina's Infinium Canine SNP20 genotyping array. The researchers' experience suggested that owners were more conducive to returning Oragene•ANIMAL kits than to agree to a blood sample. Surveys sent out with the kits also indicated that the owners found the collection to be very easy. The sample collection was successful for all participants and the process took less than 10 minutes.
High-throughput whole genome array genotyping was performed with outstanding results. The samples achieved very high overall genotype call rates (>99.5%) with very good concordance. They found that on average, genotypes from DNA derived from blood and saliva from a single dog matched >99.9% of the time*.
The researchers found the Oragene•ANIMAL DNA collection kits very favourable due to their ease-of-use and non-invasive approach, making them a preferred method of sample collection for future studies. According to the researchers: "Our results demonstrate that saliva collection from dogs is facile, convenient, and yields large amounts of high quality DNA that provide excellent performance on high-throughput whole genome arrays."
With Oragene•ANIMAL, researchers will be able to collect the number of samples required for GWAS studies and they can be confident of the quality and quantity of the DNA and its performance for array-based studies.
Want to read the full details on how Oragene•ANIMAL performed compared to whole blood in this study? Click here to link to the full report.
*Source: Yokoyama JS, Erdman CA, Hamilton SP (2010) Array-Based Whole-Genome Survey of Dog Saliva DNA Yields High Quality SNP Data. PLoS ONE 5(5): e10809. doi:10.1371/journal.pone.0010809
Oragene•DNA is well known for a number of characteristics - ease of use, non-invasive collection, high quality and quantity DNA and, of course, long term storage at ambient temperature. It's often difficult for researchers and clinicians to believe that storage at ambient temperature is possible for DNA samples. We are frequently asked about this specification of our product. However, studies using Oragene•DNA prove that customers can rely on the ability to store Oragene•DNA/saliva samples at ambient temperatures when collecting samples in remote locations, via the mail, or for event-based recruitment. The figure to the right shows an agarose gel electrophoresis of DNA extracted from Oragene•DNA/saliva samples stored at room temperature for 5 years.
The preservation and storage of DNA samples is an important consideration for molecular epidemiology, clinical trials, and population studies. To ensure your success, we have created the following best practices for the long term storage of unpurified saliva samples collected with the Oragene•DNA Self-Collection Kit. We will also highlight the rationale for these recommendations.
Storage at room temperature
DNA from saliva is stable in the Oragene•DNA collection tube for up to 5 years. This stability is achieved as a result of the kit's proprietary reagents that inactivate enzymes in saliva and minimize chemical hydrolysis of DNA. These reagents also prevent the growth of bacteria in the sample.
Frozen storage
Oragene•DNA/saliva samples may also be stored at temperatures below -20°C. Samples may undergo at least three freeze-thaw cycles with no evidence of DNA degradation. Although the Oragene•DNA collection tube is designed to ensure a tight seal, frozen storage may further reduce evaporation of the liquid medium during long term storage.
Aliquots in microcentrifuge tubes
The Oragene•DNA collection tube is designed for user friendly saliva collection from donors. However, in the lab, storage in more compact tubes may be preferable. To reduce storage space, an Oragene•DNA/saliva sample which has been heated at 50°C for a minimum of 1 hour may be split into 4 aliquots of 1 mL each and stored in 1.5 mL screw-top microcentrifuge tubes. It is advisable to use tubes with O-rings to ensure a tight seal and minimize long term loss from evaporation.
We hope these best practices will help you optimize the long term storage of all your unpurified Oragene•DNA samples. If you like this article, watch for an upcoming blog post on the best practices for long term storage of purified DNA from Oragene•DNA samples. If you want to be notified of our blog posts, be sure to subscribe to The Genetic Link.
Was this article useful? Let us know what you think by leaving a comment.
Today, DNA Genotek announced our involvement in a significant pilot project with the UK's largest bone marrow registry, the Anthony Nolan Trust. The details of this exciting project follow:
DNA Genotek, a leading provider of products for biological sample collection, stabilization and preparation, today announced that The Anthony Nolan Trust, the UK's largest bone marrow donor registry, has selected Oragene•DNA for a pilot project aimed at increasing donor recruitment. Bone marrow donor registries, also known as HLA registries, use HLA DNA testing to match leukemia patients with prospective donors. The pilot project will determine if donor recruitment can be increased significantly with the use of non-invasive, saliva-based DNA collection compared to blood collection.
The Anthony Nolan Trust has traditionally required all registry participants to have a blood sample collected either at their doctor's office or by phlebotomists at recruitment clinics. Under this pilot project, the potential donor provides a saliva sample without any assistance (for example, at home) and mails the sample back through the regular postal system, thereby facilitating and dramatically reducing the cost of the entire process. DNA samples collected with Oragene•DNA are easier, safer, and faster to collect than other methods and remain stable at ambient temperature for transport and storage prior to being analyzed at the lab.
There are currently over 400,000 people included in The Anthony Nolan Trust's registry, but many more participants are needed. 70% of patients needing a transplant cannot find a compatible match from within their families and rely on registries to find an unrelated donor for life-saving procedures. Through using Oragene•DNA, The Anthony Nolan Trust expects an increase in donor recruitment and therefore the likelihood of matches between those patients needing bone marrow transplants and potential donors held in their database.
Ailsa Ogilvie, director of operations at The Anthony Nolan Trust stated: "We have historically recruited new people to our register using blood samples, but our early laboratory results confirm that Oragene•DNA provides the high quality DNA that we need. We are optimistic that this pilot project will simplify the recruitment process and ultimately increase the number of people willing to join our register. Following the successful completion of this pilot phase, we hope to switch completely to using saliva samples to recruit new donors to our register via Oragene•DNA from late 2010."
"By streamlining the sample collection and transportation procedures, Oragene•DNA enables The Anthony Nolan Trust to focus on its primary goal of increasing donor recruitment", said Ian Curry, president and CEO, DNA Genotek, Inc. "Oragene•DNA provides a reliable, cost-effective, and scalable method that is ideal for bone marrow donor registries worldwide. Our product is easy to use, safe to transport through the mail and remains stable at ambient temperature for long periods of time. What we learn from this pilot project will help chart the future for The Anthony Nolan Trust and we are certainly proud to be part of this effort."
Note: The pilot project referenced in this press release is currently available in limited areas in the United Kingdom. It is not expected to be available nationally until the summer of 2010.
Learn more at the European Immunogenetics and Histocompatibility Conference (EFI) in Florence, Italy May 17th when Alasdair J. McWhinnie of the Anthony Nolan Trust will present a session titled: "Saliva specimens collected with Oragene are a reliable alternative to blood and buccal swabs for large scale DNA extraction and HLA typing of recruits for hematopoietic stem cell donor registries." Register here.