Clinical characteristics and genetic analysis of gene mutations in a Chinese pedigree with Peutz‐Jeghers syndrome

Peutz‐Jeghers syndrome (PJS) is a rare autosomal dominantgenetic disease, the incidence of which has been estimated to be approximately 1 in 50 000‐200 000 births,1 it is characterized by the mucocutaneous melanin pigmentation, multiple gastrointestinal polyps, and elevated risk for cancer, involving benign and malignant tumors of multiple organs both in the gastrointestinal tract and extra‐gastrointestinal sites such as lungs, breasts, ovaries, and uterine cervixes. Recent studies suggest that the mutations of the gene STK11 located on the short arm of chromosome 19(19p13.3) are important molecular bases for the pathogenesis of PJS. Multiple germline mutations and somatic mutations have been identified in PJS patients.2 However, some studies show that in some patients the STK11 was not involved in PJS,3, 4, 5 which indicates that there are still other genes may be involved in this process. One recent study reported the existence of a heterozygous pathogenic variant of the DNA repair enzyme MUTYH in PJS patients,6 yet similar kind of research in this area is still lacking. In this research, we study the genetic information in the patient and her father's peripheral blood cells to screen for the existence of germline genetic mutations using high‐throughput sequencing technology and detect the somatic gene mutation in the patient's polyp specimens. Our study aims to find types of STK11 variant in our patient and detect any other types of variant. Our results could help this family avoid a high risk of having a child with PJS by preimplantation genetic testing, and would be helpful in predicting cancer risks and provide some meaningful guidance for the clinical work.