Final report of CCQM-K86.c Relative quantification of genomic DNA fragments extracted from a biological tissue

Key comparison CCQM-K86.c was performed to demonstrate the capacity of National Metrology Institutes (NMIs) and Designated Institutes (DIs) in the determination of the relative quantity of two specific genomic DNA fragments present in a canola powder. The study provides direct support for the following measurement claim: “Quantification of the ratio of the number of copies of specified intact sequence fragments of a length up to 150 nucleotides following extraction from an unprocessed, high fat/oil ground seed matrix, with a copy number ratio from 0.001 to 1”. The study was carried out under the auspices of the Nucleic Acids Working Group (NAWG) of the Consultative Committee for Amount of Substance: Metrology in Chemistry and Biology (CCQM) and was jointly coordinated by the National Research Council of Canada (NRC) and the EU Joint Research Centre, Geel (JRC). The following laboratories (in alphabetical order) submitted measurement results in this key comparison study: Centro Nacional de Metrología, Mexico (“CENAM”); D.I. Mendeleyev Institute of Metrology, Russia (“VNIIM”); EU Joint Research Centre, Geel (JRC); Hong Kong Government Laboratory (“GLHK”); Instituto Nacional de Metrología de Colombia (“INM”); LGC (United Kingdom); National Institute of Biology, Slovenia (“NIB”); National Institute of Metrology, P.R. of China (“NIM China”/”NIMC” figures]); National Institute of Metrology, Thailand (NIMT); National Measurement Institute, Australia (“NMIA”); National Metrology Institute of Japan, AIST, Japan (“NMIJ”); National Metrology Institute of Turkey (“TÜBITAK”).JRC.F.5-Food and Feed Complianc

International Comparison CCQM K23b – Natural gas types I and III

87 p. : il.The measurement of composition of natural gas mixtures is commonly used for the calculation of its calorific value. Natural gas is a fossil fuel and its economic value per unit of volume or mass is mainly determined by its calorific value. Other aspects that might impact the economic value of natural gas, such as its sulphur content, have not been addressed in this key comparison. In most cases, the calorific value and other thermodynamical properties are calculated from composition data. At the highest metrological level, natural gas standards are commonly prepared gravimetrically as PSMs (Primary Standard Mixtures). This international key comparison is a repeat of CCQM-K1e-g. The mixtures concerned contain nitrogen, carbon dioxide and the alkanes up to butane. The only difference with CCQM-K1e-g is the addition of iso-butane to the list. This part of the comparison concerns the types I and III natural gas

An international comparability study on quantification of mRNA gene expression ratios: CCQM-P103.1

Measurement of RNA can be used to study and monitor a range of infectious and non-communicable diseases, with profiling of multiple gene expression mRNA transcripts being increasingly applied to cancer stratification and prognosis. An international comparison study (Consultative Committee for Amount of Substance (CCQM)-P103.1) was performed in order to evaluate the comparability of measurements of RNA copy number ratio for multiple gene targets between two samples. Six exogenous synthetic targets comprising of External RNA Control Consortium (ERCC) standards were measured alongside transcripts for three endogenous gene targets present in the background of human cell line RNA. The study was carried out under the auspices of the Nucleic Acids (formerly Bioanalysis) Working Group of the CCQM. It was coordinated by LGC (United Kingdom) with the support of National Institute of Standards and Technology (USA) and results were submitted from thirteen National Metrology Institutes and Designated Institutes. The majority of laboratories performed RNA measurements using RT-qPCR, with datasets also being submitted by two laboratories based on reverse transcription digital polymerase chain reaction and one laboratory using a next-generation sequencing method. In RT-qPCR analysis, the RNA copy number ratios between the two samples were quantified using either a standard curve or a relative quantification approach. In general, good agreement was observed between the reported results of ERCC RNA copy number ratio measurements. Measurements of the RNA copy number ratios for endogenous genes between the two samples were also consistent between the majority of laboratories. Some differences in the reported values and confidence intervals (‘measurement uncertainties’) were noted which may be attributable to choice of measurement method or quantification approach. This highlights the need for standardised practices for the calculation of fold change ratios and uncertainties in the area of gene expression profiling