Your DNA, Your Peptides

Your DNA, Your Peptides with Jennifer Little-Fleck A workshop on how your genome guides personalized peptide and longevity decisions ________________ Introduction Jennifer Little-Fleck: Today's presentation is called "Your DNA, Your Peptides." Whether you're new to genomics, new to peptides, or new to both, don't worry — we'll cover the basics along with some of the more important nuances of each. One of the most important things to understand is just how unique every person is. Even identical twins don't express their genetics in exactly the same way. If you're not an identical twin, the chances of having the exact same genetic code as someone else are approximately 1 in 14.5 quintillion. It's an astronomical number, and that's among unrelated individuals. Even among family members the odds are still incredibly small. When we think about optimizing longevity, wellness, or overall health, it's truly an individual process. That's especially true with peptides — what works well for one person may not be the right choice for someone else. Having a basic understanding of your own biology can be incredibly valuable. At some point, everyone asks the same questions. Why can my friend drink an espresso at 10:00 p.m. and sleep like a baby, while I have one at noon and I'm still awake at 3:00 a.m. replaying a conversation from 2009? The same idea applies to peptides. Some people try a peptide that everyone else is raving about and think, "Why didn't it do anything for me?" Understanding how your body actually works — how you process caffeine, how your stress response functions, or simply why your body responds the way it does — is genuinely useful information for everyone to have. ________________ Your Genome Is the One Input That Doesn't Change Jennifer Little-Fleck: One of the key ideas behind this presentation is that your genome is the one input that doesn't change. Everything else related to longevity can — and should — change as your health improves. Tony, you posted this week about the difference between your chronological age and your biological age, and how you're working every day to widen that gap. That's exactly the kind of progress we should be measuring. Your genome, however, is the one thing that remains constant. Your lab work should ideally be updated every 90 days, if that's available to you. Your wearable devices provide new information every day. Your supplements and peptides should evolve as your body changes and adapts. But your DNA, once sequenced, can be interpreted throughout your lifetime. Let's define a few terms. Your genome is all of your DNA — roughly three billion base pairs. About 99% of that DNA is identical from one person to another. Genomics is the science of how the variation within that DNA influences your biology and the way your body functions. The reason personalized medicine is possible is that genomics doesn't examine genes one at a time; it looks at how many genes work together. Small genetic variations begin to add up, creating meaningful patterns that influence health. Finally, we have SNPs — single nucleotide polymorphisms, the individual letter changes. That 1% of genetic variation is found within these SNPs. There are two important things to remember. First, genes set probabilities, not destinies. Second, your outcomes are influenced by both your genotype and your environment — that's why even identical twins don't necessarily follow the same life trajectory. There are four major areas that drive the longevity conversation, and those are what we'll focus on: - Lifespan and resilience - Methylation and detoxification - Oxidative stress - Growth hormone and tissue repair signaling ________________ Lifespan and Resilience: FOXO3 and APOE Jennifer Little-Fleck: When we talk specifically about longevity, two genes consistently appear in the research: FOXO3 and APOE. FOXO3 is involved in stress response and IGF-1 signaling and plays an important role in activating longevity pathways. Individuals who carry certain favorable variants of FOXO3 have been shown to have approximately 1.5 to 2.7 times greater odds of living to age 95 or older. A number of studies also suggest favorable FOXO3 variants may reduce cardiometabolic mortality, particularly in men — one reason being that these variants appear to support more efficient cellular repair. APOE is the gene many people recognize as associated with Alzheimer's disease. There are three common variants — E2, E3, and E4. The APOE4 variant is associated with an increased risk of Alzheimer's disease; individuals who inherit two copies may have a substantially higher risk if they neglect other aspects of their health. That's an important point, because carrying the gene does not mean someone will inevitably develop Alzheimer's disease — lifestyle still matters. Poor nutrition, physical inactivity, and ignoring other healthy habits can significantly increase that risk. On the other hand, the APOE2 variant has been associated with exceptional longevity. The goal isn't simply knowing which version of the gene you have — it's understanding how your body is programmed and then taking steps to support that particular genetic profile. Someone with an APOE4 variant may benefit from a different peptide strategy than someone with APOE2. ________________ Methylation: The Foundation Beneath Everything Jennifer Little-Fleck: So what do we do with that information? The first step is making sure we're supporting methylation before anything else. Methylation is upstream of nearly everything we do, including peptide therapy. If your methylation pathways aren't functioning well, you may be taking peptides without experiencing the benefits you expect. This is one reason people say, "I'm taking these peptides, but I'm not getting the same results as everyone else." In many cases their underlying biological pathways aren't functioning optimally. First, we evaluate folate metabolism, paying particular attention to the MTHFR gene, which is responsible for producing the active form of folate. If someone carries a less efficient variant, they may benefit from L-methylfolate, the active form of folate. Others may require a gentler approach — certain variants make it difficult to tolerate methylated vitamins, in which case we may recommend folinic acid instead of folic acid. Once we've identified where someone needs support, the goal is to make sure they can adequately produce SAMe — S-adenosylmethionine — because it's the body's universal methyl donor. SAMe donates methyl groups to countless biochemical pathways. If someone isn't producing enough, peptides may not produce the expected results because the body is busy addressing more fundamental needs first. Tony Medrano: I've taken SAMe for years — I'm not taking it currently — but I originally used it to support liver health and function. Was that reasonable, or was I misled? Jennifer Little-Fleck: Many of the body's functions depend on healthy methylation pathways. Whether SAMe is appropriate for you specifically depends on your genotype. Generally, when you take SAMe you're helping ensure your body has an available supply of this universal methyl donor. From there, COMT comes into play — it uses the methyl groups supplied by SAMe to support a variety of processes. One of COMT's major roles is helping clear neurotransmitters and metabolize estrogen; both men and women need healthy estrogen metabolism. COMT also helps clear many compounds through the liver, so in that sense SAMe provides an indirect benefit to liver health. ________________ Oxidative Stress: Mitochondria, ROS, and SOD2 Jennifer Little-Fleck: Suppose your mitochondria are running hot and producing large amounts of ATP. The downside is that producing a lot of energy also creates a byproduct called reactive oxygen species (ROS). Think about a campfire: you build a fire to stay warm or cook food, and it produces useful energy — but it also produces smoke. That smoke is a good analogy for reactive oxygen species. Whenever you build a fire you need good ventilation, otherwise the smoke builds up and becomes harmful. The same happens inside our cells: if ROS accumulate faster than the body can clear them, they contribute to oxidative stress. Because of this, the body relies on a gene called SOD2. The version you inherit helps determine how efficiently your body clears those reactive oxygen species. If you carry a less efficient variant, such as the SOD2 TT genotype, your body isn't as effective at clearing oxidative stress, resulting in a higher oxidative burden. Certain peptides may help support these pathways, including MOTS-c and Humanin — naturally occurring, endogenous peptides the body produces on its own. Some people produce more than others, and they can be particularly helpful for individuals with the SOD2 TT genotype. Another peptide is SS-31, also known as elamipretide, which has been approved by the FDA for Barth syndrome, a rare genetic disorder affecting mitochondrial function. SS-31 is also being studied for mitochondrial myopathy and heart failure, though those results have been mixed. MOTS-c, on the other hand, appears to be a particularly good option for people with the SOD2 TT genotype. ________________ Growth Hormone and Tissue Repair Jennifer Little-Fleck: Let's talk about CJC-1295 and Ipamorelin. You may hear people say, "I've heard this growth hormone stack is amazing, but it doesn't seem to be doing much for me." These peptides signal the pituitary gland to release your body's own growth hormone. That growth hormone travels to the liver, where it stimulates the production of IGF-1 (Insulin-like Growth Factor 1). IGF-1 is responsible for much of the tissue repair, recovery, and body-composition change people are seeking. It's really the downstream marker we should be measuring. Some individuals carry the d3-GHR variant — a deletion within the growth hormone receptor gene that can make signaling more responsive. As a result, they may experience a stronger response at lower peptide doses than someone with the full-length receptor. There are also specific IGF-1 gene variants that influence how robustly someone produces IGF-1. This is one reason people respond differently to the same protocol. Because of that, we don't simply prescribe the same dose for everyone — we recommend starting low and gradually titrating based on your IGF-1 laboratory results. Tony Medrano: And your IGF-1 response could be higher or lower based on your genetics — but it could also depend on whether the receptor has become less responsive, for example if it's being stimulated by IGF-1 all the time. Jennifer Little-Fleck: That's a really good point. We're not simply trying to push IGF-1 as high as possible; we're looking at whether the body is responding appropriately. We'll look at whether IGF-1 is changing in the lab, but we also ask: Is my body composition changing? Am I sleeping better? Am I recovering more effectively? There are also people for whom we don't want very high IGF-1 levels. For some, even a modest increase may be all they need. ________________ Slow Healers: Collagen, Inflammation, and Repair Peptides Jennifer Little-Fleck: Now consider someone who's a slow healer. Several genes influence that process. COL1A1 affects the structure and organization of collagen fibers — certain variants are associated with slower remodeling of tendons and skin. We also look at MMP genes (matrix metalloproteinases), which help build and remodel the extracellular matrix, and at IL-6 and TNF variants, which influence the inflammatory response. Inflammation is part of the repair signal, so these genes help determine whether that response is appropriately regulated. For slow healers, BPC-157 can be especially beneficial. In those cases we typically recommend longer treatment cycles rather than simply increasing the dose, and we frequently pair it with TB-500 for additional connective-tissue support. Another favorite — Tony's as well — is GHK-Cu, which can provide significant benefits for skin, hair, and wound healing. It's equally important to make sure the body has the nutrients it needs to respond. That includes adequate collagen through diet or supplements, and vitamin C is especially important. I frequently reference studies dating back to 1981 showing that people who received higher amounts of vitamin C before surgery healed much more quickly. Plastic surgeons understand this well — they routinely recommend higher vitamin C intake, especially for patients over 40, for several weeks before surgery. Glycine is another important nutrient, as it's one of the building blocks involved in skin repair and collagen production. Tony Medrano: I've heard that when collagen is taken orally, it's broken down in the stomach and isn't very bioavailable. Is that true, or is there a better way to take it? Jennifer Little-Fleck: That's still an ongoing area of debate — I've read research supporting both sides. Personally, I believe there is benefit to taking collagen orally, because historically much of the collagen in our diets came from animal foods. Well-marbled cuts of meat naturally contain collagen. That said, it's important to choose a high-quality supplement from a manufacturer that understands how to produce an effective product. The best way to know how something works for you is to treat it as an observational experiment: try it, and if you don't notice any benefit, stop. But in most cases people do experience some benefit, especially if they use it consistently for at least 90 days. ________________ Brain Health and the APOE4 Carrier Jennifer Little-Fleck: Let's return to APOE4 carriers. People often come to Tony and say, "My father had Alzheimer's disease, and I want to use peptides to help protect my brain." We know Cerebrolysin has been studied extensively in Alzheimer's disease and stroke, with some positive and some mixed results. One limitation of many trials is that they don't adequately account for differences in lifestyle and environment. Other peptides, including Selank and Semax, have also been studied and may provide neuroprotective effects and support BDNF — brain-derived neurotrophic factor — which plays a critical role in brain health and cognitive function. Maintaining healthy BDNF becomes especially important with age, particularly for APOE4 carriers. What we generally want to avoid in these individuals are aggressive growth-hormone-stimulating protocols, because excessive increases in IGF-1 may not be appropriate for people at elevated risk of Alzheimer's disease. We also want to avoid anything pro-inflammatory, since these individuals are already more susceptible to neuroinflammation, and we use caution with peptides that may negatively affect lipid metabolism, since lipid regulation is closely connected to APOE function. Tony Medrano: I remember reading that GLP-1 medications may have protective effects against Alzheimer's disease, probably because of their anti-inflammatory properties. Have you heard that? Jennifer Little-Fleck: Yes, I have heard that recently, though I need to look more closely at the research. Here's something everyone should know about the brain: the reason we're able to think and form memories is because of myelin, the protective coating around our neurons, which is composed primarily of fat, especially cholesterol. That's why I become cautious when people talk about aggressively lowering cholesterol — it plays an essential role in brain function. In fact, the brain produces its own cholesterol rather than relying on the liver's. Like everything else, you have to consider the individual's overall risk profile. If someone is on the path toward metabolic disease because of excess weight, GLP-1 medications may be tremendously beneficial. Ultimately it's about weighing potential benefits against potential risks for each person. I always say, foundation first. ________________ Longevity Peptides and Epitalon Jennifer Little-Fleck: When it comes to longevity, many people ask about Epitalon. Some say, "This is the best thing I've ever tried," while others say, "I don't really notice anything." Once you start looking at genomics, those different responses begin to make more sense. We also have to recognize there's still a limited amount of research — peptide therapy and genomics are relatively new fields. One of the best ways to maximize the benefits of peptide therapy is to make sure your methylation pathways are functioning well first, and Epitalon in particular may benefit from healthy methylation capacity. Epitalon is considered a longevity peptide because it acts as a telomerase activator. Every time your cells divide, the protective ends of your chromosomes — telomeres — become a little shorter. Telomerase helps maintain those telomeres, allowing cells to continue dividing normally for longer. To help optimize your response to Epitalon, start by supporting your methylation pathways with nutrients such as methylcobalamin (vitamin B12), L-methylfolate, glycine, and choline, depending on your needs — and continue monitoring your progress, reviewing lab results after 60 to 90 days. Tony Medrano: I just got some Epitalon, so I'll make sure my methylation pathways are supported before I start taking it. Jennifer Little-Fleck: Think of it this way: your genome is the map, and your biometrics are the cursor. I like to start with the genome and your SNP profile to understand how your body is programmed. From there we look at your labs — where is your IGF-1, what are your CRP levels (inflammation), what is your ApoB (lipid profile)? We can use tools like GlycanAge to compare your biological age with your chronological age. Then we track day-to-day metrics from wearables — heart rate variability, sleep, VO₂ max, resting heart rate. As we gather more data, we build on the strategies that are working. The scientific literature is constantly evolving; ultimately, what matters most is how you feel, along with the observational data you collect. ________________ Key Takeaways Jennifer Little-Fleck: Here are the key takeaways: - SNPs are the actionable units we evaluate within your genome. - There are four major areas we use to guide peptide selection: lifespan and resilience, methylation, oxidative stress, and growth hormone and tissue repair. - Always combine your genotype with your biometric data. If you're interested in the kind of genomic insights we've discussed, look for a clinical-grade genetic test performed through a CLIA-certified laboratory. Generally you'll have two options — whole genome sequencing, or a curated clinical panel designed for specific health applications. Whole genome sequencing is an option but tends to be more expensive; for most people I recommend a well-designed curated panel. We also offer a peptide-specific genomic test that evaluates how your biology may respond to many of the peptides currently available. Many direct-to-consumer tests, such as 23andMe or AncestryDNA, don't include all of the SNPs we evaluate for longevity and precision health, and they tend to provide very limited interpretation. If you're going to invest in genetic testing, my biggest recommendation is to have a qualified professional sit down and explain the results with you — the interpretation is just as important as the testing itself. Finally, this fits together with epigenetic age clocks. Your genome is like the hardware, while your epigenetic age is more like the software. Unlike your genome, epigenetic markers are dynamic — they change in response to sleep, nutrition, exercise, stress, and other lifestyle habits. So to leave you with one final thought: your genome is the most stable input in your longevity strategy, so use it to your advantage.