TFF3（trefoil factor 3），癌症关联基因，基因ID：7033，三叶族成员的特征是具有至少一个三叶基序拷贝，一个包含三个保守二硫化物的40氨基酸结构域。是稳定的胃肠粘膜分泌蛋白。其功能尚不明确，但可能保护粘膜免受损伤，稳定粘液层并影响上皮的愈合。这个基因在肠和结肠的杯状细胞中表达。这个基因和另外两个相关的三叶草家族成员基因在21号染色体的一个簇中被发现。Members of the trefoil family are characterized by having at least one copy of the trefoil motif， a 40-amino acid domain that contains three conserved disulfides. They are stable secretory proteins expressed in gastrointestinal mucosa. Their functions are not defined， but they may protect the mucosa from insults， stabilize the mucus layer and affect healing of the epithelium. This gene is expressed in goblet cells of the intestines and colon. This gene and two other related trefoil family member genes are found in a cluster on chromosome 21.关联癌症：乳腺癌。