CTNNB1 and tumor of parathyroid gland: Accordingly, a smaller LRP5 protein was detected by immunoprecipitation followed by Western blot analysis of the parathyroid tumors expressing the LRP5Δ666–809 transcript and in the human parathyroid tumor cell line sHPT-1 (Figure 1C), where CTNNB1 is not mutated in exon 3 [8].