c-kit外显子14突变位于蛋白的酪氨酸激酶域内。虽然在原发性胃肠道肿瘤中相对罕见，但在难治性疾病中更为普遍，提示伊马替尼抵抗的作用。与其他Kit外显子的突变不同，外显子14突变在黑色素瘤中似乎相对罕见。
c-KIT exon 14 mutations lie within the tyrosine kinase domain of the protein. While relatively rare in primary gastrointestinal tumors, they are notably more prevalent in refractory disease, suggesting a role in imatinib resistance. Unlike mutations in other KIT exons, exon 14 mutations seem relatively rare in melanoma.