Objective: To explore gene diagnosis of autosomal dominant polycystic kidney disease (ADPKD Ⅰ ),and to look for the typical mutation in order to improve the gene diagnosis. Metbods: southern blot and PCR wasused to observe the mutation condition of 3’ end single copy region of ADPKD Ⅰ gene ; Amplifying and analyzingthe microsatellite SM7 by PCR. Results: ①After the probe AH4 was hybridized with 16 patients’ genomic DNAby Southern blot, the common 15 kb fragments were found in every one; ②For 27 patients, 5. 72 kb genomicDNA, which is between the probe AH4 and JH14, was amplified by PCR, and no 5. 5 kb genomic DNA deletionwas found in this region; SM7 was amplified in lO9 health persons, its PIC was 0.76, and was closely linked towith ADPKD Ⅰ gene in three patient families. Conclusion: In Han nation, ①No large genomic DNA segmentdeletion could be found frequently in ADPKD Ⅰ gene 3’ end single copy region; ②The PIC of SM7 is high, it canbe used to make rapid gene diagnosis in about 70% ~80% ADPKD Ⅰ families. Objective: To explore gene diagnosis of autosomal dominant polycystic kidney disease (ADPKD I), and to look for the typical mutation in order to improve the gene diagnosis. Metbods: southern blot and PCR wasused to observe the mutation condition of 3 ’end single copy region of ADPKD I gene; Amplifying and analyzing the microsatellite SM7 by PCR. Results: ① After the probe AH4 was hybridized with 16 patients’ genomic DNA by Southern blot, the common 15 kb fragments were found in every one; ② For 27 patients, 5. 72 kb genomic DNA, which is between the probe AH4 and JH14, was amplified by PCR, and no 5. 5 kb genomic DNA deletion was found in this region; SM7 was amplified in 109 health persons, its PIC was 0.76, and was closely linked towith ADPKD I gene in three patient families. Conclusion: In Han nation, ①No large genomic DNA segment can be found frequently in ADPKD Ⅰ gene 3 ’end single copy region; ②The PIC of SM7 is high, it canbe used to make rapid gene diagnosi s in about 70% ~ 80% ADPKD Ⅰ families.