[The mutation character of the RET proto-oncogene in Chinese patients with Hirschsprung's disease].

To clarify the pathogenesis of Hirschsprung's disease (HD) on molecular level and to reveal the relationship between the RET proto-oncogene and Chinese patients with HD, the mutations of the RET proto-oncogene were studied in 50 Chinese patients with HD and 30 normal children with an obstipation as control. Genomic DNA was extracted from venous blood of the HD patients and the normal children. Polymerase chain reaction (PCR) products, which were amplified using specific primers (RET; exon13), were electrophoresised to analyze the single-strand conformational polymorphism (SSCP) patterns. DNA sequences of exon 13 of the RET proto-oncogene were determined in patients showing abnormal SSCP bands. And then the familial tracking research was done for the patients with Exon 13 mutation. In 50 HD patients, seven cases were found with apparently abnormal SSCP bands. And three point mutations were proved by DNA sequencing. In the parents of seven HD patients with Exon 13 mutation, two patients' fathers had the same mutation as their children. The results suggest that the mutation of the RET proto-oncogene may have a high freqency in Chinese patients with HD, especially the heterozygous point mutation. And HD has the heredity tendency.