JUL 26, 2016 07:39 AM PDT

The Case of the Disappearing Mitochondrial DNA

WRITTEN BY: Xuan Pham

Humans have two different types of DNA: nuclear and mitochondrial DNA. The one that usually gets the majority of publicity (good or bad) is nuclear DNA, which is packed into the 46 chromosomes that make us humans. But floating inside of the cytoplasm are mitochondria, the proverbial "powerhouse of the cell" that also carry DNA. In contrast to nuclear DNA, mitochondrial DNA (mtDNA) is much shorter, coding for 37 discreet genes, and is packed into circular structures. Each mitochondrion is estimated to contain between 2 to 10 copies of the circularized mtDNA.

Mitochondrial DNA is also uniquely inherited from females. It turns out, any traces of mtDNA in a male's sperm is usually destroyed upon fertilization with the egg. This means all the mtDNA floating in all of us can, theoretically, be traced back to the first female - a person scientists call "Mitochondrial Eve."

While we don't know exactly why evolution selected for mtDNA from only the mom's side, scientists are making headway into solving the case of the disappearing mtDNA on the dad's side. Watch the video to find out more!
About the Author
  • I am a human geneticist, passionate about telling stories to make science more engaging and approachable. Find more of my writing at the Hopkins BioMedical Odyssey blog and at TheGeneTwist.com.
You May Also Like
OCT 30, 2018
Plants & Animals
OCT 30, 2018
The Science Behind Cat Landings
You’ve undoubtedly heard the old wives’ tale that cats always land on four feet, and while they do most of the time, there’s a lot more t...
NOV 07, 2018
Videos
NOV 07, 2018
The Threat of Neglected Tropical Diseases
Did you know that around one billion people suffer from a neglected tropical disease?...
NOV 19, 2018
Videos
NOV 19, 2018
The Amazon's worst enemy
Brazil has a new leader, and he could be the Amazon’s biggest enemy yet. President Jair Bolsonaro has pledged to sell off large portions of the rainf...
NOV 26, 2018
Health & Medicine
NOV 26, 2018
The Fight Bite
  Human bite wounds are a common source of polymicrobial infections accounting for many emergency room visits. One bacteria, Eikenella corrodens, ...
NOV 25, 2018
Videos
NOV 25, 2018
What If Earth Spun the Other Way?
If once upon a time the Earth spun the other way—the seasons wouldn’t change because of the Earths tilt. But, what would change is the climate ...
NOV 26, 2018
Videos
NOV 26, 2018
How to get rid of jet lag
Have you ever gone on an amazing trip somewhere only to have it totally ruined by jet lag? Jet lag is what we experience when our internal clocks are throw...
Loading Comments...