[ensembl-dev] why does ensembl have multiple dbSNP records for the same locus

[Andrea Edwards]

Please scratch this question - i did not see in my data that they were 
snps can't be unambiguously mapped.

Of course if anyone has anything further to add, it's always welcomed

thanks

On 29/11/2010 17:16, Andrea Edwards wrote:
> Hi
>
> I have written a program to get all of the cow snps from ensembl 
> present in dbSNP. When i examine these snps i find some chromosome 
> loci have multiple dbSNP records. In other words if i do something like
>
> select count(*) distinct chromosome, locus from snps
>
> i get less than the total number of snps obtained
>
>
> Why is this? Is this something to do with ensembl or dbSNP. I thought 
> dbSNP merged all submitter records (ss) into one rs record for each 
> chromosome locus. So i was expecting one dbSNP record per snp. I 
> thought perhaps it might a representation of the snp in a different 
> database but i have been informed that the only variations for cow in 
> ensembl are from dbSNP.
>
> thanks a lot