IN SILICO SCREENING FOR PHENOTYPE-ASSOCIATED EXPRESSED SEQUENCES

摘要

The present invention provides methods for determining whether a nucleic aci d sequence is a marker for a phenotype or cell type of interest which comprise s providing a database of expressed sequence tag sequences (EST's) from the species; placing said EST's in groups termed clusters based on homology of EST's within each cluster; determining for each cluster the total number of EST"s within said cluster; ordering said clusters sequentially based on the number of EST's in each cluster; dividing said ordered clusters into subrang es based on the number of EST's per cluster; determining for each cluster subrange obtained from step (e) the number EST's within said cluster which a re expressed in said predetermined cell type of interest; calculating according to a normal distribution the number of clusters in each subrange expected to contain a predetermined threshold percentage of EST's expressed in said cell type of interest, wherein said threshold percentage is a percentage from abo ut 10% to about 100%; determining the number of clusters in each subrange observed to contain said predetermined threshold percentage of EST's express ed in said predetermined cell type; and identifying subranges having an observe d number of clusters that meet said predetermined threshold percentage greater than thenumber of clusters expected to meet said predetermined threshold percentage for the subrange according to normal distribution; wherein if the percentage of EST's expressed in said cell type of interest in a cluster identified is equal to or greater than said predetermined threshold percentage, the cluster contains a nucleic acid that is a marker for the cel l type of interest.