We have compared the clinical features of ADPKD caused by mutations at the PKD1 locus (linked to the alpha-globin complex on chromosome 16) with those of disease not linked to the locus (non-PKD1).
Our results show that to avoid misinterpretation it is important to investigate the occurrence of an alpha-gene deletion when polymorphisms situated in the alpha-globin locus are used for linkage studies on ADPKD.
The results show that APKD is closely linked to the PGP locus on the short arm of chromosome 16 (16p13----p12), which is consistent with the previously reported linkage both to PGP and to the alpha globin locus.
Hitherto, mutations that lead to autosomal dominant adult-type polycystic kidney disease have been found to be linked to the alpha-globin genes on the short arm of chromosome 16.
In these families, linkage analysis was carried out with a cloned DNA sequence from the alpha-globin locus known to be closely linked to the disease gene in adult onset ADPKD.
Hence we have searched for a linkage marker for APCKD; we show here that the APCKD locus is closely linked to the alpha-globin locus on the short arm of chromosome 16 (zeta = 25.85, theta = 0.05).
Further study showed that the phosphoglycolate phosphatase locus is also closely linked to both the locus for adult polycystic kidney disease and the alpha globin gene cluster.