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Comprehensive molecular diagnostics are highly dependent on the technical performance of next-generation sequencing (NGS) pipelines, which are assessed by data quality, cost, turnaround time, and accuracy of detecting a range of sequence and copy number variants. A dataset of 285 clinically validated cases (205 retrospective and 80 prospective), carrying complex sequence and copy number variants and thousands of genetic polymorphisms underwent a clinical validation of the KAPA HyperChoice target enrichment system with parallel sample fidelity assessment across a number of NGS panels. The analysis included assessment of peripheral blood, urine, muscle and FFPE tissues. High-quality and exceptionally uniform data with 100% coverage of all targeted panels were obtained, resulting in complete sensitivity and specificity for all variant types across nearly all panels and tissue types. Overall reduction in cost and turnaround times was obtained with the implementation of a parallel genotyping sample fidelity system. Results of the laboratory quality improvement study focused on a single NGS pipeline that includes both nuclear and mitochondrial genomes demonstrated utility in the clinical setting to assess a range of referral reasons, necessary due to the complex molecular etiology of human genetic disorders, while reducing costs and turnaround times. [ABSTRACT FROM AUTHOR]

A design idea of fidelity sampling cylinder while drilling based on surface nitrogen precharging and supplemented by downhole pressurization was proposed, and the working mode and optimization method of sampling parameters were discussed. The nitrogen chamber in the sampling cylinder functions as an energy storage air cushion, which can supplement the pressure loss caused by temperature change in the sampling process to some extent. The downhole pressurization is to press the sample into the sample chamber as soon as possible, and further increase the pressure of sample to make up for the pressure that the nitrogen chamber cannot provide. Through the analysis of working mode of the sampling fidelity cylinder, the non-ideal gas state equation was used to deduce and calculate the optimal values of fidelity parameters such as pre-charged nitrogen pressure, downhole pressurization amount and sampling volume according to whether the bubble point pressure of the sampling fluid was known and on-site emergency sampling situation. Besides, the influences of ground temperature on fidelity parameters were analyzed, and corresponding correction methods were put forward. The research shows that the fidelity sampling cylinder while drilling can effectively improve the fidelity of the sample. When the formation fluid sample reaches the surface, it can basically ensure that the sample does not change in physical phase state and keeps the same chemical components in the underground formation.

Formation sampling while drilling (FSWD) technology has become a research hotspot in oilfield development at home and abroad. The technology is characterized by a comparatively short operation time. Since the operation time is short, the obtained formation data are closer to the real situation in the reservoir. After the formation fluid enters the sample chamber from the sampling module, sealed, and returns from the downhole to the surface, the change in ambient temperature and pressure causes the sample volume to shrink and the sample pressure to decrease correspondingly. The change in temperature and pressure leads to irreversible phenomena such as phase transformation or degassing, which can affect the quality analysis of the sample. To avoid the phenomenon, the pressure in the sample chamber is maintained above the bubble point pressure by pre-charging nitrogen on the ground and boosting adjustment in the downhole, so that the formation sample fluid is consistent with the phase state in the original formation when it is retrieved from the ground. The described method is used to provide results close to the real parameters in the reservoir. As the pre-charged nitrogen and the final sample occupy different cavities of the same vessel, and the volume of the vessel is constant, the change in the parameters, including the sampling volume, temperature difference, and pressure difference between the ground and the well bottom, will cause a change in the pressure of the pre-charged nitrogen. Therefore, the problem of ensuring sample fidelity has become the key to sampling technology. To solve the problem, the method of combining ground pre-charged nitrogen pressure with downhole sample chamber pressurization has been introduced. [ABSTRACT FROM AUTHOR]