A novel method for room temperature distribution and conservation of RNA and DNA reference materials for guaranteeing performance of molecular diagnostics in onco-hematology: A GBMHM study

Abstract

Objectives: Performance of methods used for molecular diagnostics must be closely controlled by regular analysis of internal quality controls. However, conditioning, shipping and long lasting storage of nucleic acid controls remain problematic. Therefore, we evaluated the minicapsule-based innovative process developed by Imagene (Evry, France) for implementing DNA and RNA controls designed for clonality assessment of lymphoproliferations and BCR-ABL1 mRNA quantification, respectively.

Design & methods: DNA samples were extracted from 12 cell lines selected for giving specific amplifications with most BIOMED-2 PCR tubes. RNA samples were extracted from 8 cell line mixtures expressing various BCR-ABL1 transcript levels. DNA and RNA were encapsulated by Imagene and shipped at room temperature to participating laboratories. Biologists were asked to report quality data of recovered nucleic acids as well as PCR results.

Results: Encapsulated nucleic acids samples were easily and efficiently recovered from minicapsules. The expected rearrangements at immunoglobulin, T-cell receptor and BCL2 loci were detected in DNA samples by all laboratories. Quality of RNA was consistent between laboratories and met the criteria requested for quantification of BCR-ABL1 transcripts. Expression levels measured by the 5 laboratories were within ±2 fold interval from the corresponding pre-encapsulation reference value. Moreover aging studies of encapsulated RNA simulating up to 100 years storage at room temperature show no bias in quantitative outcome.

Conclusions: Therefore, Imagene minicapsules are suitable for storage and distribution at room temperature of genetic material designed for proficiency control of molecular diagnostic methods based on end point or real-time quantitative PCR.

Keywords: Chronic myelogenous leukemia; Cytogenetics and molecular genetics; Laboratory hematology; Lymphoproliferative disorders; Minimal residual disease.