Failure to find linkage between a functional polymorphism in the dopamine D4 receptor gene and schizophrenia

Abstract

We report the results of a linkage study in 24 families multiply affected with schizophrenia using a polymorphic DNA sequence encoding the third cytoplasmic loop of the dopamine D4 receptor. Two‐point LOD score analyses with a range of single gene models ranging from near dominant to near recessive revealed no evidence for linkage. In addition, we examined the data by non‐parametric sib‐pair analysis and found no excess sharing of alleles between affected sib‐pairs. We therefore conclude that mutations within the dopamine D4 receptor gene do not have a major aetiological role in schizophrenia in our collection of pedigrees.