Castle Biosciences, Inc., a molecular diagnostics company, provides test solutions for the diagnosis and treatment of dermatologic cancers, Barrett's esophagus (BE), uveal melanoma, and mental health conditions. The company offers DecisionDx-Melanoma, a risk stratification gene expression profile (GEP) test that predicts the risk of metastasis for patients with uveal melanoma; DecisionDx-SCC, a risk stratification test for cutaneous squamous cell carcinoma; MyPath Melanoma, a diagnostic GEP test for use in patients with difficult-to-diagnose melanocytic lesions; and TissueCypher, a risk stratification spatial-omics test to predict future development of progression of high-grade dysplasia and/or esophageal cancer in patients with non-dysplastic, indefinite dysplasia, and low-grade dysplasia BE. It also provides DecisionDx-UM, a risk stratification GEP test that predicts the risk of metastasis for patients with uveal melanoma; and IDgenetix, a pharmacogenomic test that helps guide optimal drug treatment for patients diagnosed with major depressive disorder, schizophrenia, bipolar disorder, anxiety disorders, social phobia, obsessive-compulsive personality disorder, post-traumatic stress disorder, and attention deficit hyperactivity disorder. The company offers its products to skin cancer and gastroenterology markets. The company was incorporated in 2007 and is headquartered in Friendswood, Texas.