Linkage analysis of schizophrenia to chromosome 15

We have mapped a sample of 68 families consisting of one or more affected s ibling pairs with schizophrenia or schizoaffective disorder with 20 markers spanning all of chromosome 15 to investigate whether there is a locus on c hromosome 15 that confers an increased susceptibility to schizophrenia usin g parametric and nonparametric linkage analyses. Allele sharing identical b y descent and multipoint maximum likelihood score (MLS) statistics were emp loyed. Results show excess allele sharing for multiple markers in 15q11.2-q 25, a chromosomal region previously found linked to a decrease in the norma l inhibition of the P50 auditory-evoked response to the second of paired st imuli, a decrease associated with schizophrenia. Excess allele sharing was found for markers spanning about 48 cM in 15q11.2q25 (D15S1002-D15S1023). T he greatest single point allele sharing was found at D15S659 (62.6%). The m ultipoint MLS scores were greater than 1.0 in the 30-52 cM interval delimit ed by ACTC and D15S150, with a maximum value of 2.0 with GENE-HUNTER PLUS n ear D15S1039. (C) 2001 Wiley-Liss, Inc.