Comparison of two linkage inference procedures for genes related to the P300 component of the event related potential

Our goal was to detect genes contributing to the P300 component of the even t related potential (ERP). We found that all of the ERP traits were highly correlated. Most of them distinguished alcoholics from nonalcoholics. To ha ve one summary variable for the ERP traits, we calculated the first princip al component(PRIN1). After adjusting for age and sex, we screened for linka ge of PRIN1 to all of the markers using the two-point Haseman-Elston sib-pa ir test. We compared results obtained from computing a moving average of tw o-point p-values ("regional" inference) in an approximately 10 cM region wi th those obtained from single, two-point tests. Different "suggestive" and "significant" linkage regions were found using the two methods. Based on th e regional method, areas on chromosomes 2 and 5 should be followed up in fu ture studies. (C) 1999 Wiley-Liss, Inc.