EVX1 (even-skipped homeobox 1) is a transcription factor that plays critical roles in early embryonic development and respiratory system formation. The protein contains a homeodomain closely related to the Drosophila even-skipped gene and functions as a transcriptional repressor through its carboxyl-terminal proline/alanine-rich region 1. EVX1 is essential for early post-implantation development, as targeted disruption in mice causes embryonic lethality shortly after implantation, with failure to form proper extraembryonic tissues and egg cylinders 2. In respiratory development, EVX1 is required for specification of the pre-Bötzinger complex neurons, which are crucial for respiratory rhythm generation 3. The gene is located on chromosome 7 at the 5' end of the HOX1 locus and is transcribed in opposite orientation to adjacent HOX genes 4. In cancer contexts, EVX1 shows tumor suppressor characteristics in esophageal squamous cell carcinoma (ESCC), where its underexpression correlates with lymph node metastasis and tumor invasiveness 56. Additionally, genome-wide association studies have identified EVX1 variants associated with resistant hypertension, suggesting roles in cardiovascular pathways 7.