An efficient linkage analysis strategy for autosomal dominant polycystic kidney disease.

BACKGROUND

Autosomal dominant polycystic kidney disease (ADPKD) is one of the most common inherited renal disorders in the world. Mutations in PKD1 are responsible for 80-95% of all autosomal dominant polycystic kidney disease (ADPKD). Although the need for linkage analysis of ADPKD is decreasing after the success of mutation detection at whole exons of PKD1, linkage analysis still has some advantages in detecting non-PKD1 families, thereby avoiding hopeless mutation analysis.

METHODS

We evaluated ten microsatellite markers beside or inside PKD1 on chromosome 16p. Allele frequency and heterozygosity of each marker were calculated based on the 100 genotypes obtained from 50 normal Japanese. Automated microsatellite genotyping using ABI Prism 377 and GeneScan software was applied. Markers were mapped using radiation hybrid mapping. Finally, this strategy was applied in the linkage analysis of 6 independent Japanese ADPKD families.

RESULTS

D16S3024, D16S3082, D16S3027 and D16S423 showed high heterozygosity (> 0.80) in a normal Japanese population and sufficient proximity to the PKD1 gene for linkage analysis. We could successfully analyze 144 genotypes within 7 hours. This strategy produced theoretically near-maximum LOD scores in 4 independent Japanese families inheriting ADPKD.

CONCLUSIONS

Automated genotyping using microsatellite markers, D16S3024, D16S3082, D16S3027 and D16S423 are very useful in the linkage analysis of ADPKD.