Quick overview of what you’ll learn from this blog post:
- What epigenetic methylation testing is and why it’s important
- DNA methylation and its role in regulating gene expression
- CpG’s ability to impact epigenetic changes
- Current advancements in epigenetic methylation testing
Epigenetic Methylation is one of the key underlying mechanisms that drive biological changes in the body at a cellular, genetic, and even molecular level. Testing this involves taking DNA, identifying where methylation has occurred, then using complex processing technology and algorithms to either match the changes to specific genes, or create a bigger picture of an overarching process in the body, like biological aging.
There are epigenetic algorithms designed to spot key changes or patterns that correlate to disease risks, or to detect phenotypes like an individual’s weight loss response to caloric restriction. There are also algorithms that look at much larger, complex biological processes, like biological aging.
Let’s dive further into what Epigenetic Methylation even is, and why it’s important to learn about.
Epigenetics Modifies Gene Expression
Epigenetics is how your body regulates and changes what genes are being read and enacted, and which ones are skipped over.
All of your DNA holds the same giant list of recipes and instructions. Epigenetic modifications like methylation allows your body to pick and choose which instructions to read, which instructions need a bit of tweaking, and which ones to skip over, depending on the circumstances.
While genetics studies heritable changes in gene activity or function due to the direct alteration of the DNA sequence, epigenetics studies heritable changes in gene activity or function that is not associated with any change of the DNA sequence itself.
Although nearly all cells in an organism contain the same genetic information, not all genes are expressed simultaneously by all cell types. In a broader sense, epigenetic mechanisms regulate the wide variety of gene expression profiles in cells, tissues, and wider systems in multicellular organisms.
Because DNA Methylation is specific to cell type, cells from different tissues will have different patterns of methylation. The brain, for instance, contains some of the highest levels of DNA methylation of any tissue in the body. It is meticulously regulated.
What is DNA Methylation?
DNA Methylation changes how the gene’s instructions are read by the body by adding methyl molecule ‘stickers’ onto and around that gene. More technically, DNA Methylation is a stable epigenetic mark that can be inherited across multiple cell divisions. Demethylation is the process of removing some of those stickers, reverting the gene’s instructions to their original form.
If your DNA was a big recipe book for every part of your body, then your genes are the written instructions detailing the specific steps for all your body’s different recipes. Methylation is the act of adding methyl ‘stickers’ on top of the written instructions. These methyl molecule stickers can block off part of the instructions, so the body can’t read what’s under it. When it’s time to read that gene’s instructions. The body only works with the parts that are visible. If enough methylation stickers are added onto a step, or methylation covers the part of a gene that would allow your body to begin reading it, then that gene’s instructions could be skipped over entirely.
For example, human infants need to be able to produce enzymes to digest milk. All mammals normally have this gene in their DNA. However, many animals lose the ability to digest milk, and become lactose intolerant as they mature into adults. For them, drinking milk as an adult causes gastric distress because their body no longer produces a crucial digestive enzyme (Lactase). As mammals mature, their body identifies the gene responsible for saying ‘Create Lactase’ and gradually lowers its expression. Some people maintain high levels of that enzyme throughout their lives because their gene isn’t suppressed, while other people have lactase production stopped early, from a fairly young age.
Your body naturally uses methylation throughout your entire life to regulate genetic expression. During development and cell differentiation, DNA methylation is at its highest dynamic state. It peaks during early development, but the shifting patterns of methylation continue to change throughout adulthood. It plays a key role in mammalian development, differentiation, and maintenance of cellular identity and function, through the control of gene expression and by extension, the creation of proteins.
Over the past 40 years, changes in DNA methylation have been observed in many human diseases, especially cancer. Precise regulation of DNA methylation is essential for nearly every part of the body’s cellular functions and relationships. Changes to DNA methylation can create sweeping changes in the body’s phenotypes and propensity toward certain diseases.
What is a CpG?
A CpG is a spot on your DNA (where a piece of DNA called cytosine is right next to a piece called a guanine.) That specific spot is where methyl molecules can ‘stick’ onto your DNA, and create epigenetic changes.
There are about 29 million CpGs known in the human genome, and 60-80% of them are methylated to some degree. Approximately 45% of the mammalian genome consists of transposable and viral elements that are silenced by bulk methylation (Schulz et al, 2006). If these elements were to be demethylated and fully expressed, replication of viral genetics present in DNA can lead to gene disruption and DNA mutation. So, it is important that methylation and demethylation is managed appropriately by the body.
Epigenetic Methylation Testing Today
Due to the hard work of scientists around the world, we have a well-mapped human genome, and the scientific community is working on figuring out what each gene does. This is additionally complicated by epigenetics. Because methylation can change the instructions written on a gene, a single gene can actually code for several different proteins, each with different functions and shapes, depending on how that gene is methylated.
As researchers continue to dive into epigenetic methylation testing, we learn more and more about how methylation can change genetic expression, how that impacts our body, and even how our own lifestyle changes can impact methylation – and therefore expression of phenotypes.
However, this field of study is still very new. As scientists discover more about methylation and how all of these complex biological processes all fit together, sometimes older algorithms or older conclusions are shown to be incomplete, or are replaced with a new algorithm that does its job much more accurately and precisely.
If you want to try epigenetic testing for yourself, get started here. After collecting and sending your blood sample (finger prick), TruDiagnostic’s lab will extract your DNA, map out the methylation patterns on around 900,000 key CpG locations, and provide you with a suite of reports using a variety of algorithms for a whole-body picture of aging. One of TruDiagnostic’s primary goals is to create a ‘Rosetta Stone’ of methylation. They want to help map out the patterns of methylation – what each pattern does, how it’s influenced by our experiences, and how it influences us.
This blog was written in partnership with TruDiagnostic. TruDiagnostic is a Health Data company, specializing in epigenetic testing & research. They use a multi-omic approach to help scientists, physicians, and patients understand and benefit from the information found in the fluid epigenome.
The primary focus for TruDiagnostic is DNA Methylation – they offer a variety of algorithms and lab services for researchers, physicians, and consumers who want the most accurate and insightful longevity analysis from a CLIA-certified and HIPAA-compliant lab.
TruDiagnostic began with TruAge – a test that measures Biological Age by looking at Methylation. They now provide a full suite of aging related metrics. This includes telomere length measurements, intrinsic and extrinsic age calculations, immune cell subset deconvolution, current pace of aging, and more. It is available through AgelessRx here.