This study investigated pathogenic genes associated with non-syndromic cleft lip with or without cleft palate (NSCL/P) through transcriptome-wide association studies (TWAS). By integrating expression quantitative trait loci (eQTL) data with genome-wide association study (GWAS) data, we identified key susceptibility genes, including KLC1. Notably, the variant rs12884809 G>A was linked to an increased risk of NSCL/P by enhancing the binding of the transcription factor ELK1 to the KLC1 promoter, thereby upregulating its expression. This alteration in KLC1 expression subsequently impacted mitophagy, leading to significant changes in cellular behavior and zebrafish morphology. Our findings illuminate the genetic mechanisms underlying NSCL/P and provide valuable insights for future prevention strategies and a deeper understanding of this condition.