Subjects were excluded if they had an Axis I diagnosis, active or recent substance abuse, or if they had a first-degree relative with a known or suspected Axis I disorder based on family history questionnaire. Controls were 52.2% female, had a mean age of 48.4 ± 18.6 years and an estimated IQ of 105.0 ± 12.4. All subjects were Caucasian by self-report and drawn from a single geographic location (Glen Oaks, NY area). Although population stratification is a potential confound in any case-control study, we have previously demonstrated that undetected substructure is not present in our

geographically homogeneous population. In a genome-wide association buy KU-55933 study of a case-control cohort collected by the same methods described above ( Lencz et al., 2007), we tested for stratification using 210 ancestry informative markers selected for maximal informativeness and observed no differences between patients and controls beyond chance levels. Moreover, none of the subjects in the cohort deviated from a single population as assessed by the STRUCTURE program ( Pritchard et al., 2000). Patient diagnosis was

established through structured interview (Structured Clinical Interview-DSM-IV; SCID-IV) ( First et al., 1998) and confirmed by diagnostic consensus conference, which utilizes expert clinical opinion alongside SCID-IV data and corroborating medical record information. Healthy controls for the project were assessed using the Structured Clinical Interview for DSM-IV, MLN8237 nmr Non-Patient

edition, specifically designed for healthy subjects to rule out Axis I diagnoses. In addition to the structured diagnostic interview, potential subjects were screened to rule out any history of CNS trauma, neurological disorder, or diagnosed learning disability. FEZ1 genotyping procedures were carried out using the Affymatrix 500K platform as previously described ( Lencz et al., 2007). Briefly, genomic DNA was extracted from whole blood and hybridized to two chips containing ∼262,000 and ∼238,000 SNPs based on manufacturer’s specifications. Patients and controls were proportionally Oxalosuccinic acid distributed on each 96-well plate. Genotype calls were made using Bayesian Robust Linear Model with Mahalanobis distance classifier algorithm threshold at 0.5 applied to batches of 100 samples. Mean call rates <90% on both chips, or <85% on one chip, were rejected, resulting in a mean call rate for the retained sample of 97%. Allele frequencies, Hardy-Weinberg equilibrium (HWE), and linkage disequilibrium structure were examined using Haploview 3.32 ( Barrett et al., 2005). The four SNPs formed a single haplotype block as shown in Figure 6A. For FEZ1 association with illness, none of the four SNPs in the haplotype deviated from HWE (p > 0.05). χ2 test statistics were used to test for allelic and genotypic associations to schizophrenia for single SNPs, as well as for group differences on haplotype frequencies.