Received June 20, 2003; revisions received March 12 and July 1, 2004; accepted July 28, 2004. From the Human Genome Research Center, Department of Biology, Institute of Biosciences, and GREA, Interdisciplinary Group of Studies on Alcohol and Drugs, Institute and Department of Psychiatry, Medicine Faculty; and Department of Parasitology, Institute of Biomedical Sciences, University of Sao Paulo, Brazil; and the Section of Genetics, Division of Psychological Medicine and SGDP Research Centre, Institute of Psychiatry, Kings College London, De Crespigny Park, London. Address correspondence and reprint requests to Dr. Zatz, Human Genome Research Center, Department of Biology, Institute of Biosciences, University of Sao Paulo, Rua do Matão, Travessa 13, Number 106, Cidade Universitária CEP:05508-090, Sao Paulo SP, Brazil; email@example.com (e-mail). Supported in part by the Fundação de Amparo a Pesquisa do Estado de São Paulo and Conselho Nacional de Desenvolvimento Cientifico e Tecnológico. The authors thank Constância Urbani, Patrícia Hochgraf, Antonia Cerqueira, and Elisangela Quedas.