Whey Acidic Protein Staining Method

**Semantic type:** Laboratory Procedure

**Definition:** An immunohistochemical technique to identify whey acidic protein (WAP), a major whey protein secreted in rodent's milk. WAP promoter has been used for targeting heterologous genes to the mammary gland. The technique is used in diagnostic histopathology to identify breast cancer.

**Synonyms:** - WAP Staining Method