Consistent with Wiegand et al.7, we also observed a portion of clear cell carcinomas without ARID1A mutations showed a loss of ARID1A protein expression, suggesting that epigenetic silencing, posttranscriptional and posttranslational regulation as well as genomic alterations might be important for the loss of ARID1A protein expression in clear cell carcinoma. The gene discussed is ARID1A; the disease is clear cell adenocarcinoma.