SRY (Sex Determining Region Y)-Box 10 (SOX-10), also known as transcription factor SOX-10, is a nuclear transcription factor that acts in regulation of embryonic development and in the specification and differentiation of cells of melanocytic lineage. During development, SOX10 first appears in the forming neural crest and continues to be expressed in Schwann cells. It is important for differentiation, maturation and maintenance of Schwann cells and melanocytes. SOX-10 is diffusely expressed in neurofibromas and schwannomas, and mutations in the SOX-10 gene are linked to Waardenburg-Shah and Waardenburg-Hirschsprung disease. It is also detected in melanocytes and epithelial cells of salivary gland and mammary gland. Anti-SOX-10 has been shown to be sensitive for conventional, spindled, and desmoplastic melanoma, and has been used to detect metastatic melanoma and nodal capsular nevus in sentinel lymph nodes.