三葉族成員的特征是具有至少一個三葉基序拷貝，一個包含三個保守二硫化物的40氨基酸結構域。是穩定的胃腸粘膜分泌蛋白。其功能尚不明確，但可能保護粘膜免受損傷，穩定粘液層并影響上皮的愈合。這個基因在腸和結腸的杯狀細胞中表達。這個基因和另外兩個相關的三葉草家族成員基因在21號染色體的一個簇中被發現。
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.