Single Nucleotide Polymorphisms or SNP- why do they matter?
July 11th, 2022
What is a SNP?
The actual definition is: A single nucleotide polymorphism, or SNP (pronounced "snip"), is a variation at a single position in a DNA sequence among individuals. Recall that the DNA sequence is formed from a chain of four nucleotide bases: A, C, G, and T. If more than 1% of a population does not carry the same nucleotide at a specific position in the DNA sequence, then this variation can be classified as a SNP.
If a SNP occurs within a gene, then the gene is described as having more than one allele. In these cases, SNPs may lead to variations in the amino acid sequence. SNPs, however, are not just associated with genes; they can also occur in noncoding regions of DNA.
Although a particular SNP may not cause a disorder, some SNPs are associated with certain diseases. These associations allow scientists to look for SNPs in order to evaluate an individual's genetic predisposition to develop a disease. In addition, if certain SNPs are known to be associated with a trait, then scientists may examine stretches of DNA near these SNPs in an attempt to identify the gene or genes responsible for the trait. (Nature Education site)
Why is this relevant to you or your family?
As we gain genomic knowledge regarding what genetic code does what inside the cell and body, then we have a learning point from which to assess what a SNP could do for a certain gene's expression.
For example, there are genes associated with apolipoprotein E that carry the designation APOE 3, 4 or 5 based on the SNP. These genes are associated with increased Alzheimer's disease as the APOE4 genotype is found more frequently. This is a direct association and is helping us learn how to mitigate this risk potentially through diet and lifestyle changes. On the other hand, toll like receptor 4, TLR4, activity was believed to be related to worsened Covid risk. If a person had an altered copy of one of the two gene copies, then the function of that gene could be significantly reduced leading to worsened viral surveillance capabilities. This knowledge could help us understand who has a higher risk of diseases like SARS2. When it was studied in vivo, it turned out to be a minimal to moderate risk for more severe disease. (Taha et. al. 2021) (Aboudounya et. al. 2021)
For a deep dive into current SNP's and Covid risk, read the Frontiers in Immunology article by Grolmusz.
Overall, we want to pay attention to our genes in the future as this information becomes available for all of us. I have run these tests on myself and found very useful information for disease mitigation over time. This is just an FYI for all of you.
However, if you wanted to start this process now you would need to:
1) get a 23 and Me test run
2) take the raw genomic data to a website like foundryfitness or pure genomics and merge them in their online platforms
3) take the information to a genome literate provider to review with you
Still learning and growing,