|
 |
 |
|
|
|
 |
|
|
5. Repercussion effects
Although deciphering the draft sequence of the human genome revealed that the human genome contains about 30 thousand genes23), the functions of most genes remain un-clarified. Before the emergence of DNA microarrays, it was not possible to compare various genes at the same time. DNA microarrays enable researchers to simultaneously detect genes expressed under various disease conditions, such as cancer, and clarify the mechanisms of disease development. In 1999 Lander et al. reported that a use DNA microarrays enabled to classify cancer types more accurately than traditional histological methods24). S.H. Friend et al. used DNA micro arrays to analyze primary breast tumors of 117 patients and found that certain patterns of gene expression profiles strongly suggest clinical metastasis at later stage, indicating a use of DNA microarray gene expression profiling as a diagnostic tool for later stage metastasis25). DNA microarrays are also used to detect small differences in genes (single nucleotide polymorphism, SNP) between individuals, which correspond to expressed differences in individuals26, 27). SNP research is very important, because it can lead to tailor-made medicine, in which an individual can be diagnosed and treated according to his or her own genetic information. DNA microarrays have also been used in the field of agriculture for the purposes of effective breeding and increasing tolerance to the environment as information of plant genomes and cDNAs have been accumulating. The ability to use DNA microarrays to collect global gene expression data quantitatively and systematically has opened up an entirely new field of computational biology.
Commercialization of the GeneChip array and the promotion of self-made DNA microarrays by disclosing information on the Internet have synergistically prompted the wide-spread use of DNA microarrays. According to market analysis, the market for DNA microarrays was $400 -550 million dollars in 200028, 29). The share of commercial arrays is 41% and that of the self-made arrays is 39% of the total market. Twenty percent of end-users use both types28). The main player in the commercial microarray market is Affymetrix. As academic institutions and pharmaceutical companies move to more aggressively adopt microarrays and prices start to come down, the market is expected to grow to $1-2.2 billion dollars in 200528, 29).
|
|
|
