Genomic approaches to the genetics of alcoholism

When studying complex diseases such as alcoholism that develop as a result of numerous genetic and environmental factors, researchers can use the sequence data that have become available both for the human and for animal genomes. For these analyses, investigators are being aided by efforts to identify and characterize functionally relevant DNA sequences in the entire genomic DNA sequence--a process called annotation. Various bioinformatics and annotation tools can help in this enterprise. These include four primary approaches: (1) precomputed, annotated public Web sites that provide a plethora of information; (2) in-house analyses from which users can choose the appropriate analyses for their purposes; (3) Web-based annotation systems that analyze a user's DNA sequence; and (4) private resources that provide access to annotated genomic sequences at cost. In addition to careful study of the DNA sequence for clues about function, expression studies of mRNA levels using gene chips provide information about the activity levels of thousands of genes that may vary in different tissues, different animals and people, or under different environmental conditions.