What’s the answer? (duplicate dbSNP IDs)

BioStar is a site for asking, answering and discussing bioinformatics questions. We are members of the community and find it very useful. Often questions and answers arise at BioStar that are germane to our readers (end users of genomics resources). Every Thursday we will be highlighting one of those questions and answers here in this thread. You can ask questions in this thread, or you can always join in at BioStar.

This week’s highlighted question is….

Repeated rsIDs in dbSNP?

Is it possible that rsID is repeated in dbSNP? I recently downloaded dbsNP130 from UCSC came across cases such as

chr10 50325 50326 0 + G G G/T genomic single by-cluster 0 0 unknown exact 3

chr18 4739 4740 + G G G/T genomic single by-cluster 0 0 unknown exac

Is this expected? And what’d be the explanation? Or, have I made an error in downloading parsing file?

learnerforever

I highlighted this one because it seems to come along fairly frequently (as evidenced by Jorge Amigo’s answer. And we find it surprises people who have just noticed that the UCSC Genome Browser is now separating out a set of SNPs from dbSNP that they call the Mult. SNPs(132) track you can see on their browser. I think it’s a good awareness to have about these SNPs.

Check out the answers in full here.