USP42 and neoplasm: Instead, the PMS2 deficiency of both appears to be caused by loss of heterozygosity (LOH)/allelic imbalance (AI) at this locus based on changes in VAF between blood and tumor of known polymorphisms in PMS2 and adjacent genes, including SDK1 (MIM *607216), RBAK-RBAKDN, TNRC18, AIMP2 (MIM *600859), USP42 and ZNF12 (MIM *194536) (Table S1).