Examples of mesothelin mRNA expression in hen ovaries containing tumors and in normal ovaries. (A) mRNA was detected with hen specific primer based on the predicted hen mesothelin sequence. Mesothelin mRNA expression was identified in 1/4 (25%) endometrioid tumors, 3/4 (75%) serous carcinomas, 2/6 (33%) mucinous carcinomas, and 6/7 (86%) mixed histology tumors. Mesothelin was not detected in normal ovaries. (B) Measurement of mesothelin mRNA expression using differential density analysis with the loading control β-actin used as a reference. Samples are in the same order in A and B.