Tuesday, July 24, 2007
I just received an email from one of my readers today. Trip said " am med student at Univ of KY, interested in medical genetics and have been reading your blog.........I am recommending http://www.snpedia.com/ for a blog post on the gene sherpa" Well Trip....You Asked for it, You got it..... As they say on that old Toyota commercial....
First I would like to mention that my friend Bertalan over at ScienceRoll commented on this Yesterday. He did an excellent job. Also SNPedia has their own blog although there are only 2 posts so far.....
So Single Nucleotide Polymorphisms (SNPs) are little genetic changes, much like letters in a word. There is some data out there which shows taht when readign a senetnce letters in the middle of a word do not alter the readers undertsanding. This could be the case for a SNP, it may result in no change in the protein function. Or it could be the case that a SNP may change the word altogether.
Even crazier is when a SNP isn't even in the coding region of a protein. This may affect a protein as well. When we make mRNA there is a process called splicing. This splicing could be altered by a SNP located in an intron (noncoding region of a gene) or it could be located in an another gene and affect the protein by epistasis........
Listen, this is all confusing. Much like SNPs are...... It reminds me of other "genetic markers" like HLA haplotypes. No one knows what role HLA B27 has in ankylosing spondylitis....it is just linked to an increased likelihood of having the disease.
So what about SNPedia. This is a catchy idea. There exist several databases out there including OMIM. However, the more databases, the better. If we can cross reference these for validity it certainly would be nice.
In reviewing SNPedia I performed searches on several SNPs including in TCF7L2 and CCR5. The database has listed some but not all of the associations within each of these "genes" in fact CCR5 is not only an HIV associated gene, it is also implicated in abdominal aneurysms.
The Sherpa Says:
Any database is only as good as the data in the base. I feel that opening it up to public contribution through wiki is a great idea. However, we must assure the public that SNPedia will be monitored by a knowledgeable set of curators.