SNAP-ChIPâ (Sample Normalization and Antibody Profiling for Chromatin Immunoprecipitation) utilizes pools of DNA-barcoded designer modified nucleosomes (dNucs) as quantitative spike-in controls for ChIP-Seq normalization and antibody specificity testing.
Using this new approach, many commonly used ‘ChIP-grade’ antibodies failed due to significant cross-reactivity with other histone PTMs, including some of those recommended by the ENCODE consortium. These results highlight the need for internal controls to monitor antibody performance in each ChIP experiment, and position SNAP-ChIP as the new gold standard for antibody validation in ChIP.
“The results are striking and will have an immediate impact on the field”, said Dr. Michael Christopher Keogh, Chief Scientific Officer at EpiCypher and a corresponding author on the study. “Our ongoing investigations demonstrate that ChIP-incapability, despite what their datasheets promise, is a widespread issue for histone PTM antibodies, and highlights a critical need for re-evaluating these reagents”.
EpiCypher is using SNAP-ChIPâ technology to screen hundreds of commercially available antibodies to identify those with best-in-class performance. These “SNAP-ChIPâ certified antibodies” are available now from EpiCypher and their use will be essential to provide a renewed confidence in data generated using ChIP.