Humanity began with a common genetic ancestor about 200,000 years ago, then spread across the Earth. A combination of that migration and thousands of generations created diversity in our species. But some of that variation is also due to genetic mutation.
When we hear mutation, people think either of debilitating disorders or comic book superpowers. While superheroes aren’t yet a reality, some human mutations may be beneficial and others cause no serious detriment.
Here are 14 common human mutations you might have or know someone who does.
1. Lactose tolerance
While many in the West take drinking milk for granted, most people around the world stop drinking milk when they reach adulthood as they lose the ability to digest it. But around 10,000 years ago, as Europeans domesticated cows, a mutation in the MCM6 gene caused some people to keep producing the enzyme lactase, allowing them to drink milk. Other farming communities that domesticated cattle, such as one in India, separately evolved the ability to digest milk, too.
2. Gluten-intolerance/Celiac disease
Farming and agriculture introduced humans to new proteins about 10,000 years ago. Gluten is a protein present in wheat, but this protein cannot be completely broken down into amino acids like other proteins. Gluten is broken down to the peptides gliadin and glutenin. People with mutations of the HLA gene react to these peptides, giving rise to classic symptoms of gluten intolerance like diarrhea, stomach cramps, fatigue and abdominal bloating. Celiac disease is a severe form of gluten intolerance found to affect 1% of the population. Non-celiac gluten sensitivity is a mild form of gluten intolerance. In India, more than 10% of the population has gluten intolerance.
3. Color blindness
Around 0.5% of women and 8% of men have color blindness. This means they see colors in a different way than most people. There are three common forms of color blindness: Deuteranomalia, Tritanopia and Protanopia. Most color vision problems are inherited and present at birth.
Geneticists have yet to nail down the exact gene(s) that cause testosterone related baldness, but they do know it is the result of human mutation.
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