Response to "Determining Allele-Specific Protein Expression (ASPE) Using a Novel Quantitative Concatamer Based Proteomics Method".

A recent publication in this journal reported the application of a targeted proteomic strategy using a quantitative concatemer (QconCAT) standard to the assessment of allele-specific expression of UGT2B15 claiming this methodology to be a "novel" approach ( J. Proteome Res. 2018, 17 (10), 3606-3612, DOI: 10.1021/acs.jproteome.8b00620). While the application is not common, the method was previously described and reported by our group in relation to the quantification of CYP2B6 alleles ( J. Proteome Res. 2013, 12 (12), 5934-5942, DOI: 10.1021/pr400279u) to assess the expression of a prevalent polymorphism in a Caucasian population.