A hygromycin resistance cassette replaced 2.9 kb of the upstream promoter region, exon 1 and part of intron 1. Southern blot confirmed a smaller product size and immunoprecipitation indicated no detectable protein. However, LrCaptureSeq data indicates that deletion of this region disrupts isoforms A, A2, and C but leaves isoform B intact. (J:92068, J:293375)