And why are we getting so sick?
Disease is exploding and that means some genome of ours — DNA or mtDNA — must be rapidly changing. In the last 50 years, modern disease (Alzheimer’s, dementia, cancer, diabetes, etc.) has increased exponentially. Which genome could be the culprit?
In Mito #1 and Mito #2, we learned that humans have two genomes. In fact, we all descend from a long line of women that can be traced back to eastern Africa over 150,000 years ago. By sequencing our mitochondrial DNA (the “other genome”), researchers reconstructed our origins based on the ancient migrations of women. Put simply, by tracking moms, we learned how she migrated and adapted to new environments, adjusted her energy management systems and passed that knowledge down (via her mitochondrial DNA) to her children.
Let’s take a Squint.
Studies of the Nuclear Genome
It turns out that our nuclear genome (you know, the 10th grade biology, Watson and Crick, classic double helix structure) has gotten a ton of attention in recent years. Thanks to the Human Genome Project, we are learning more than we ever have before about our nuclear genome. In fact, they were able to take one of the most important Squints in history to explore and generate the first sequence of the human genome.
The Human Genome Project was an international scientific research project with the goal of determining the base pairs that make up human DNA, and of identifying, mapping and sequencing all of the genes of the human genome from both a physical and a functional standpoint. Launched in October 1990 and completed in April 2003, the Human Genome Project’s signature accomplishment – generating the first sequence of the human genome – provided fundamental information about the human blueprint.
So what did the blueprint tell us?
Same Same
What is interesting, when you take a further Squint, is that despite all of the best sequencing data we’ve learned, our DNA blueprint hasn’t changed that much. Our genes are almost identical to chimps. It’s hard to believe, but it’s true! Of course, we look radically different (thank you frontal lobes!), but we are very closely related by DNA.
In fact, human’s share 98.9% of their DNA with chimpanzees. Humans, chimps and bonobos descended from a single ancestor species. As humans and chimps gradually evolved from a common ancestor, their DNA passed from generation to generation too. What the research is telling us is that, despite important distinctions we can see between ourselves and chimpanzees, we share high genetic similarity.
From a nuclear perspective, we haven’t changed that much.
What Genome is Changing?
We now know that our well-mapped and beautifully sequenced nuclear DNA hasn’t changed much. So where does that leave us? If our DNA hasn’t changed significantly, what genes are changing so rapidly to account for such an accelerated rate of the diseases we are currently experiencing?
Genes go wrong and cause disease. We know that. But if our “genes” haven’t changed that much, how could our DNA be responsible for all that is going bad with our health? We keep blaming what “runs in the family”, but those DNA “genes” seem to be holding steady, relatively unbroken. Where is modern sickness coming from?
The Next Step: Keep Squinting!
The answers to these questions may be found in the “other” genome. We’ve spent quite some time exploring the double helix over the years. Is it time for the mitochondrial genome to have her moment? We think so! This genome is the one we inherit from mom-only, that has been quietly and fearlessly detecting and protecting us from our environment, adapting to changes, providing us energy, and passing those adaptive changes down to us.
Let’s keep Squinting and learn more about what we already knew: mom’s are amazing!