Genetics of event-related brain potentials in response to a semantic priming paradigm in families with a history of alcoholism

Event-related brain potentials (ERPs) are altered in patients with a variet y of psychiatric disorders and may represent quantitative correlates of dis ease liability that are more amenable to genetic analysis than disease stat us itself. Results of a genomewide linkage screen are presented for amplitu de of the N4 and P3 components of the ERP, measured at 19 scalp locations i n response to a semantic priming task for 604 individuals in 100 pedigrees ascertained as part of the Collaborative Study on the Genetics of Alcoholis m. N4 and P3 amplitudes in response to three stimuli (nonwords, primed word s [i.e., antonyms], and unprimed words) all showed significant heritabiliti es, the highest being .54. Both N4 and P3 showed significant genetic correl ations across stimulus type at a given lead and across leads within a stimu lus, indicating shared genetic influences among the traits. There were also substantial genetic correlations between the N4 and P3 amplitudes for a gi ven lead, even across stimulus type. N4 amplitudes showed suggestive eviden ce of linkage in several chromosomal regions, and P3 amplitudes showed sign ificant evidence of linkage to chromosome 5 and suggestive evidence of link age to chromosome 4.