EGFR Exon 21 Mutation

**Semantic type:** Cell or Molecular Dysfunction

**Definition:** A molecular genetic abnormality indicating the presence of a mutation in exon 21 of the EGFR gene.

**Synonyms:** - EGFR Exon 21 Gene Mutation - ERBB Exon 21 Mutation - ERBB1 Exon 21 Mutation - Epidermal Growth Factor Receptor Gene Exon 21 Mutation - HER1 Exon 21 Mutation