Mast cell tumours (MCT) have been documented in numerous species and mutations within the KIT proto‐oncogene are implicated in the neoplastic biology of mast cells in humans, dogs and cats. This study determined high KIT gene nucleotide and Kit amino acid sequence homology between several species known to suffer mast cell neoplasia and especially high sequence conservation between the cheetah (Acinonyx jubatus) and domestic cat (Felis catus) KIT sequences. As a result, we hypothesised that KIT mutations would exist in the neoplastic DNA of four cheetahs diagnosed with MCT from a recent case series. PCR and Sanger sequencing identified conservative exon 6 KIT mutations in two of the four cheetahs. The mutations were different between the two cheetahs. Only wild‐type DNA in exons 6, 8, 9 and 11 of KIT was observed in the MCTs of the remaining two cheetahs. Twenty cutaneous MCTs from domestic cats were collected for KIT mutation comparison. Twelve tumours possessed a mutation within KIT exons 6, 8 or 9 (60%, 95% CI 38.5%‐81.5%). No mutations were detected in exon 11. There was no significant association between domestic feline MCT KIT mutation status and tumour histological grade (traditional schematic, P = .934; Sabattini 2‐tier schematic, P = .762) or mitotic index (P = .750). KIT mRNA and Kit protein sequences are conserved across species but the role of KIT in feline MCT pathogenesis is not completely understood.

中文翻译：

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猎豹（Acinonyx jubatus）和家猫（Felis catus）肥大细胞肿瘤中的KIT突变

肥大细胞瘤 (MCT) 已在许多物种中得到证实，并且KIT 原癌基因中的突变与人类、狗和猫肥大细胞的肿瘤生物学有关。本研究确定了已知患有肥大细胞瘤的几种物种之间的高KIT基因核苷酸和 Kit 氨基酸序列同源性，尤其是猎豹 ( Acinonyx jubatus ) 和家猫 ( Felis catus ) KIT序列之间的高度序列保守性。因此，我们假设最近一个病例系列中四只被诊断为 MCT 的猎豹的肿瘤 DNA 中存在KIT突变。PCR 和 Sanger 测序鉴定出保守的外显子 6 KIT四只猎豹中的两只发生了突变。两只猎豹的突变不同。在其余两只猎豹的 MCT 中仅观察到KIT外显子 6、8、9 和 11 中的野生型 DNA 。收集来自家猫的 20 个皮肤 MCT 用于KIT突变比较。12 个肿瘤在KIT外显子 6、8 或 9内具有突变（60%，95% CI 38.5%-81.5%）。在外显子 11 中未检测到突变。家猫 MCT KIT突变状态与肿瘤组织学分级（传统示意图，P  = .934；Sabatini 2 层示意图，P  = .762）或有丝分裂指数（P  = .750）。成套工具mRNA 和 Kit 蛋白序列在物种间是保守的，但KIT在猫 MCT 发病机制中的作用尚不完全清楚。