Abstract: Wang Changyuan*, Liu Hua, Zong Jinbao, Liu Shiguo, Shi Tongxin. *Department of Dermatology, Qingdao Municipal Hospital, Qingdao 266011, China Corresponding author: Shi Tongxin, Email: shitx2006@163.com 【Abstract】 Objective To study the mutation of STK11 gene in a Chinese family and a sporadic patient with Peutz-Jeghers syndrome （PJS）, and to provide a basis for genetic diagnosis and counseling. Methods One sporadic patient and two patients from a family with PJS were collected, all of whom had typical mucosal pigmentation and gastrointestinal polyposis. Blood samples were obtained from the two patients and six unaffected relatives in this family, the sporadic patient, and 100 healthy controls. DNA was extracted, and PCR was performed to amplify nine exons and their adjacent introns in the STK11 gene followed by direct sequencing. The sequencing results were aligned to the published sequence of STK11 gene from Genbank. Results No mutation was found in the STK11 gene of any of the patients, unaffected relatives, or healthy controls. Conclusions Genetic heterogeneity exists in Peutz-Jeghers syndrome, hinting that there may be other causative genes or sites for this entity.

Key words: Peutz-Jeghers syndrome, Gene, STK11, Mutation