Background

What is dbASM?

Many people are familiar with dbSNP, NCBI’s public resource for information on SNP’s. Genapha/dbASM aims to be a public resource for information on ASM. dbASM is also a collection of web-based tools to help researchers in studying ASM. These tools sit on top on a database built of publicly-available information, such as the GRCh37.p10 human reference genome, HapMap genotype and methylation data, and eventually 1000 Genomes data.

So then, what is ASM and why should we care?

ASM stands for Allele-Specific Methylation. Methylation is the addition of a methyl group to something. Allele-Specific Methylation means that the methylation only happens when a certain allele is expressed at a SNP.

So, if our hypothetical SNP can either be A or C and we have the C allele, this C allele *could* be methylated. If we have the A allele, then it won’t be. Thus, the methylation is allele-specific. This is in contrast with other methylation that can happen on the much larger scale of genes, or a region of the chromosome. As a side-note, dbASM is currently only geared towards exploring C methylation, which we have some pre-existing data on already. And as a further side-note in addition, that’s the idea behind the logo at the top of the page.

We care about ASM, because this addition of a methyl group to a C nucleotide followed by a G can regulate the expression of our genome. And although ASM may not be the underlying causative mechanism for some diseases or phenotypes, by studying it we can better understand genetics and we might be able to predict risk factors for those conditions.