The SMARCA4 gene is located in the chromosome 19p13.2 encoding for BRG1 protein and loss of function mutations to this gene alone can lead to the formation of small cell carcinoma of the ovary-hypercalcemic type, uterine sarcomas, sinonasal undifferentiated carcinomas, and gastrointestinal tract pleomorphic carcinomas. This evidence concerns the gene SMARCA4 and sinonasal undifferentiated carcinoma.