No proof of linkage between schizophrenia-related disorders including schizophrenia and chromosome 2q21 region.

We examined linkage between schizophrenia and schizophrenia-related disorders and five genetic markers on chromosome 2 in fourteen families ascertained through affected probands in St. Louis and Vienna. The chromosomal region 2q21 was considered a candidate locus for schizophrenia because of a report of a balanced translocation 2;18 (q21;q23) in a schizophrenia family. Linkage analyses were conducted for three disease models: a narrow model including schizophrenia only; an intermediate model including a spectrum of schizophrenia-related disorders; and a broad model including major affective disorders. Multipoint linkage analyses excluded linkage across the region (about 50 cM) for the intermediate disease model. The same was generally true for the broad affection status model. None of the two-point and multipoint analyses showed definite linkage of schizophrenia to any marker. The most prominent positive association was between D2S44 and a broad affection status model, giving a two-point lod score of 1.71 at 0.20 recombination fraction.