Evaluation of linkage of maskers on chromosome 6p with schizophrenia in Taiwanese families

Previous studies have indicated possible linkage of schizophrenia with chro mosome 6p21-24, In an attempt to replicate these findings, we studied the l inkage of schizophrenia with nine markers on chromosome 6p21-24 in 39 Taiwa nese schizophrenic nuclear families with at least two affected siblings, Tw o diagnostic models (narrow: Diagnostic and Statistical Manual of Mental: D isorders-IV schizophrenia only; and broad: including schizophrenia, schizoa ffective, and other nonaffective psychotic disorders) were used to define t he disease phenotypes. With the broad and narrow diagnostic models, the mar ker D6S296 produced maximum two-point lod scores of 1.46 (theta = 0.2) and 1.35 (theta = 0.2), respectively, in the recessive inheritance model. Assum ing locus heterogeneity, a multipoint lod score of 0.85 was obtained betwee n markers D6S296 and D6S277 under the narrow/recessive model. Maximum nonpa rametric lod scores of 1.25 (p = 0.09) and 1.36 (p = 0.08) were observed, b ut still not statistically significant, at D6S296 in the narrow and broad d iagnostic models, respectively. Both two-point analysis of the dominant mod el (lod score 0.85) and nonparametric analysis (lod score 1.25) showed a mi ld peak lod score appeared at marker D6S 285 as well. The results add some support to the suggestive linkage of schizophrenia with markers in the regi ons of chromosome 6p22 and 6p24 in an ethnically distinct Taiwanese sample. Am, J.Med. Genet. (Neuropsychiatr. Genet.) 96:74-78, 2000 (C) 2000 Wiley-L iss, Inc.