ABSTRACT
Human genetic variation is most frequently seen as single-nucleotide polymorphism
(SNP). Many of these have been discovered more or less by chance when comparing
sequence trace files of overlapping contigs from different individuals. A more systematic
approach by comparative sequencing in a defined group of individuals by the SNP consor-
tium has now greatly improved our understanding of genetic variation. SNP coverage
across the human genome is not random and may be completely absent in highly
conserved regions or highly abundant in other regions where genetic diversity is biologi-
cally important. Large-scale association studies by genotyping many individuals by many
single SNPs are considered to be the most promising method to identify the cause of
complex diseases. In addition, it will also improve the understanding of the individual
response to drugs, also termed pharmacogenetics.
