locus heterogeneity in APKD

There is locus heterogeneity in APKD with at least three loci
identified by linkage studies and two genes cloned. The gene
for APKD1 on chromosome 16p encodes a protein called
polycystin-1, which is an integral membrane protein involved in
cell–cell/matrix interactions. The protein encoded by the gene
for APKD2 on chromosome 4 has been called polycystin-2.
Mutation analysis is not routinely undertaken, but linkage
studies may be used in conjunction with ultrasound scanning to
detect asymptomatic gene carriers.