I am a clinician, and have no particular expertise in genomics. I'm confused by much of what I see on dbSNP. Any help would be greatly appreciated! Thank you in advance.

I need some help understanding HGVS Names!

I see SNP's referred to with conventions like **A66G** for MTRR ([rs1801394][1]) and **A1298C** for MTHFR ([rs1801131][2]).

When I look under **HGVS names** for rs1801394 I see: NM_002454.2:c.66A>G, which l assume equals "A66G", but there are many other "names" there. What are these names? Are they all equivalent?

When I look under **HGVS names** for rs1801131 I do not see anything resembling "A1298C". Does this mean I have the wrong rs# for this SNP?

According to [SNPedia][3], it's the correct rs#: "rs1801131 is a SNP in the MTHFR gene, representing an A>C mutation at mRNA position 1298".

 [1]: http://www.ncbi.nlm.nih.gov/projects/SNP/snp_ref.cgi?rs=1801394
 [2]: http://www.ncbi.nlm.nih.gov/projects/SNP/snp_ref.cgi?rs=1801131
 [3]: http://www.snpedia.com/index.php/Rs1801131
the 1298 in A1298C must be relative to the mRNA, which includes the 5' UTR, or maybe just based an earlier prediction as to where the CDS began. I would imagine there is some historical reason it is still known by that name.

Here is one of many papers where they discuss c.665C>T and c.1286A>C: http://www.nature.com/gim/journal/v15/n2/full/gim2012165a.html

HGVS coding nomenclature starts from the CDS start, and is transcript specific, hence NM_005957.4:c.1286A>C is the HGVS identifier for this mutation. As long as you include the c-dot people will know what you mean.