Is there any database to get the mutated gene sequence responsible for breast cancer or we have to generate our own mutated sequence using SNP database?
The COSMIC database may have what you're looking for.
It has information on these genes, e.g. http://www.sanger.ac.uk/perl/genetics/CGP/cosmic?action=byhist&s=4&hn=carcinoma&sn=breast&ln=BCAR3 -- but it was not found to be mutated in the samples they have
As others have pointed out, there is no single "mutated gene sequence responsible for breast cancer".
If you're looking for SNPs that increase susceptibility to the disease, a good starting point is OMIM. You can search with a simple term (e.g. "breast cancer") to get started. Then, click on the tab that says "OMIM dbSNP" to limit results to those loci with a known SNP. View a gene from the list of results and you'll see a "SNP" link in the links box on the right of the page, which will take you to dbSNP entries - e.g. this page for BRCA1.
You can also do all of this programmatically, but I'd learn the basics of how the website works first.
Try the International Cancer Genome Consortium site. The data is new and still flowing in, but worth checking. The data portal is http://dcc.icgc.org/ , but for a grasp of the whole project see the main site: http://icgc.org/
'...mutated gene sequence responsible for breast cancer...'
that simply doesn't exist. So there is also no database.
Your HolyGrail is hosted by NHGRI here http://research.nhgri.nih.gov/projects/bic/
Use of this site constitutes acceptance of our User Agreement and Privacy Policy.
version 2.3.6
What do you really mean ? You want a repository of known mutations that cause breast cancer ? Which genes are you interested in ? Precise and clarify your question so that people can try to help you.
i need mutated breast cancer genes for my analysis.. so i m bit confused whether there is an existing database which consists of sequences having mutations in it.