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bioRxiv · 10.1101/2024.08.06.606813

Variability of 7K and 11K SomaScan plasma proteomics assays

Candia, J.·Fantoni, G.·Delgado-Peraza, F.·Shehadeh, N.·Tanaka, T.·Moaddel, R.·Walker, K. A.·Ferrucci, L.
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Abstract

SomaScan is an aptamer-based proteomics assay designed for the simultaneous measurement of thousands of human proteins with a broad range of endogenous concentrations. The 7K SomaScan assay has been recently expanded into the new 11K version. Following up on our previous assessment of the 7K assay, here we expand our work on technical replicates from donors enrolled in the Baltimore Longitudinal Study of Aging. By generating SomaScan data from a second batch of technical replicates in the 7K version, as well as additional intra- and inter-plate replicate measurements in the new 11K version using the same donor samples, this work provides useful precision benchmarks for the SomaScan user community. Beyond updating our previous technical assessment of the 7K assay with increased statistics, here we estimate inter-batch variability, we assess inter- and intra-plate variability in the new 11K assay, we compare the observed variability between the 7K and 11K assays (leveraging the use of overlapping pairs of technical replicates), and explore the potential effects of sample storage time (ranging from 2 to 30 years) in the assays precision.

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Candia, J., Fantoni, G., Delgado-Peraza, F., Shehadeh, N., Tanaka, T., Moaddel, R., Walker, K. A., Ferrucci, L.. 2024-08-08. Variability of 7K and 11K SomaScan plasma proteomics assays. https://doi.org/10.1101/2024.08.06.606813

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