NIJMEGEN, Netherlands — Are you left or right-handed? The answer may have a lot to do with your genes. Researchers in the Netherlands have discovered that tubulins — unique proteins that build the internal skeletons of cells — also influence which hand is dominant.
A team from the Max Planck Institute for Psycholinguistics examined rare genetic variants from the genomes of more than 350,000 people during their study. Specifically, they wanted to find clues proving that certain aspects of our DNA influence which hand we end up favoring for basic tasks — such as writing or picking up your morning coffee. This led to the discovery that tubulins play a role in determining left-right brain asymmetry.
During the embryonic stage of human development, study authors explain that the left and right sides of the brain get wired differently. These differences lead to people having specific preferences as they grow, such as which side they lean to when they hug, which side of their mouth they tend to chew on, and which hand holds a pen or pencil.
The team adds that the left hand is dominant for just 10 percent of the world population.
A previous study from 2020 found 48 common gene variants connected to left-handedness. Most were in the non-coding regions of the DNA. Researchers say these included sections which may control genes related to tubulins.
In this new study, Clyde Francks, a geneticist and neuroscientist at the Max Planck Institute, notes that tubulins are long, tube-like filaments that control the shapes and movements of cells. These microtubules appear to influence which hand is dominant because they form cilia — hair-like objects in the cell membrane that direct the flow of fluids during human development.
Francks’ team analyzed the genetic data from 313,271 right-handed and 38,043 left-handed individuals during this project. That analysis discovered variants in a tubulin gene, TUBB4B, that was 2.7 times more likely among left-handed individuals.
Despite only affecting a small number of the people in this study, rare genetic variants “can give clues to developmental mechanisms of brain asymmetry in everyone,” Francks says in a statement.
The researchers believe their new findings may pave the way for future work which determines how microtubules give an “asymmetric twist” to early brain development. The study is published in the journal Nature Communications.
My grand baby sucks his left thumb,from birth. Now 4 yrs. Old seems to have a photographic memory. He does everything lefty,- sports, writing, eating, etc. He doesn’t seem to get it confused living in a right handed world. He’s crazy smart ( but all grammas say that)
1. For left handers to be so rare,it’s crazy that 3 of my 4 sons are left handed! My dad was also left handed.
I’m the only left handed person in my family.
There is 1 left handed cousin in each family of my parents siblings.
My husband and I are both left handed.
Same for me. And I’m almost 75 now. No lefty’s on either side of family!
I enjoy this publication. I too am left handed as well as able to use my right hand. I was forced to use my right hand at an early age because my folks thought it to be taboo to use my left hand. Thanks to my parents, teachers, I am able to use both hands effectively.I have a brother left handed as well as my baby son, a nephew and also a grandson that uses both hands like me. This grandson is very inquisitive. He plays mahjong on his tablet and does very well.
I am the only left-hander in my family. I have 2 siblings and numerous cousins.
I’d be curious to know if one nationality has more lefties than others.
Signed: a German lefty.
I am left handed. Write left handed. I started cake decorating as an adult and after several years I realized I write with my right hand on cakes.
I paint with either hand and eat. I can switch hit playing softball. Cut right handed. Shoot right handed. With a bow I use my left. What does that mean in this research?
Of 7 siblings, 3 of us are left handed. Both parents were right handed. Go figure.
What about Bi- dexterous people?
I’m 77, I write and eat with my right hand but I can’t make an 8 except with 2 circles…….. with my left hand I do drinks and pouring and carrying, and I do sports, games, drive and I can do a figure 8 with my left hand at a 1st grade level. No interchange!!!
What’s the story about people who started as a left using their left hand but as a child parents made them right handed
I am left handed. Only one I know in my family. Growing up I was slapped with a ruler at school, forcing me to write with my right hand. Over the years I am dominantly left hands in writing, cutting meat etc. however, when I play any sports I do so right handed. When I have to write on a blackboard or whiteboard it is with my right hand.
I write use spoon and fork left handed. I am not 100% lefty. I do kick left foot. I throw and bat right handed. I do say I’m a lefty because I have all the same everyday problems as all left handed people do.
I’m exactly the same as you Jerry. Also my grandfather and my dad and I are left handed. All three b-days within a week of each other.