Scientists have identified the genes linked to left-handedness

For the first time, scientists have identified the genetic differences associated with...

Posted: Sep 5, 2019 9:39 AM

For the first time, scientists have identified the genetic differences associated with left-handedness, a trait found in 10% of the human population.

What's more, those genetic variants result in differences in brain structure, which might mean that left-handed people have better verbal skills than the right-handed majority.

While previous research into twins has indicated that genes are at least partially responsible for controlling handedness, the new study, conducted by scientists from the University of Oxford and published in the journal Brain, is the first to identify which genetic variants separate the lefties from the righties.

The research could suggest a potential correlation between left-handedness and superior verbal skills, said Akira Wiberg, a Medical Research Council fellow at the University of Oxford who worked on the study.

"This raises the intriguing possibility for future research that left-handers might have an advantage when it comes to performing verbal tasks, but it must be remembered that these differences were only seen as averages over very large numbers of people and not all left-handers will be similar," he said in a news release.

Further research must be conducted to test this potential advantage, according to Gwenaëlle Douaud, joint senior author of the study and a fellow at Oxford's Wellcome Centre for Integrative Neuroimaging.

"We need to assess whether this higher coordination of the language areas between left and right side of the brain in the left-handers actually gives them an advantage at verbal ability. For this, we need to do a study that also has in-depth and detailed verbal-ability testing," she said.

Genetic regions

Funded by the UK's Medical Research Council and Wellcome, a UK medical research charity, the researchers studied the DNA of 400,000 people, including 38,332 left-handers, from the UK Biobank, a database comprising the health information of volunteers across the country.

They isolated four genetic regions associated with left-handedness; three of those regions were linked to proteins that influence brain structure and development. Specifically, the proteins were connected to microtubules, a component of cell "scaffolding" or the cytoskeleton.

The cytoskeleton determines the structure of cells, as well as the way they operate within the body. Previous research has demonstrated the cytoskeleton's influence on "left-right asymmetry" in other species.

"Many animals show left-right asymmetry in their development, such as snail shells coiling to the left or right," Douaud said.

By analyzing brain imaging from about 10,000 of the people studied, the researchers found that the genetic variants related to left-handedness were associated with differences in the brain's white matter tracts -- in particular, the tracts that connect the areas of the brain associated with language.

What's more, Douaud told CNN, the research indicated that in left-handed people, "the left and right sides of the brain communicate in a more coordinated way.

Left-handed people demonstrate "a higher synchronization of the natural oscillations of your brain, and these oscillations still happen when you are idle," she said, a synchronization that occurs "precisely again in the brain regions dedicated to language."

The study also indicated an association between the aspects of brain development linked to handedness and the likelihood of developing schizophrenia or Parkinson's disease.

Dominic Furniss, joint senior author alongside Douaud and a fellow at Oxford's Nuffield Department of Orthopaedics, Rheumatology, and Musculoskeletal Science told CNN, "It has long been known that there are slightly more left-handers amongst patients with schizophrenia than the general population. By contrast, there are slightly less left-handers with Parkinson's disease than the general population."

The new research, Furniss said, "suggests that these diseases, along with handedness, are the product of fundamental differences in brain development, some of which is driven by genes."

The researchers stressed, however, that the association between handedness, schizophrenia and Parkinson's indicates only correlation, not causation, and that the difference in terms of the number of people with the illnesses is very slight.

Indiana Coronavirus Cases

Data is updated nightly.

Confirmed Cases: 32078

Reported Deaths: 2004
CountyConfirmedDeaths
Marion9268539
Lake3320168
Cass15826
Allen130966
St. Joseph120534
Hendricks113067
Hamilton111592
Johnson1086104
Elkhart105728
Madison58258
Porter49021
Bartholomew48133
Clark46138
LaPorte41522
Tippecanoe3753
Jackson3671
Howard36519
Delaware35735
Hancock32127
Shelby31521
Floyd31438
Boone28835
Morgan26224
Vanderburgh2482
Montgomery23117
White2268
Decatur22431
Clinton2221
Grant19121
Noble18921
Harrison18721
Dubois1852
Greene16724
Warrick16426
Dearborn16421
Henry1619
Monroe16011
Vigo1477
Lawrence14423
Miami1391
Putnam1337
Jennings1274
Orange12422
Scott1183
Ripley1126
Franklin1068
Kosciusko941
Carroll922
Daviess8216
Steuben802
Marshall761
Newton7410
Wabash722
Wayne715
Fayette684
LaGrange602
Jasper581
Washington521
Fulton471
Rush452
Jay440
Randolph433
Jefferson411
Whitley402
Pulaski390
Clay391
Owen341
Brown331
Sullivan321
Starke313
DeKalb311
Perry260
Huntington262
Knox250
Tipton251
Benton250
Wells240
Crawford230
Blackford211
Switzerland190
Fountain182
Spencer171
Posey170
Parke170
Gibson142
Ohio130
Warren121
Adams121
Vermillion90
Martin90
Union80
Pike60
Unassigned0154
West Lafayette
Clear
70° wxIcon
Hi: 83° Lo: 68°
Feels Like: 70°
Kokomo
Clear
70° wxIcon
Hi: 79° Lo: 65°
Feels Like: 70°
Rensselaer
Clear
68° wxIcon
Hi: 87° Lo: 65°
Feels Like: 68°
Fowler
Clear
68° wxIcon
Hi: 79° Lo: 65°
Feels Like: 68°
Williamsport
Clear
70° wxIcon
Hi: 80° Lo: 66°
Feels Like: 70°
Crawfordsville
Broken Clouds
65° wxIcon
Hi: 80° Lo: 66°
Feels Like: 65°
Frankfort
Clear
69° wxIcon
Hi: 81° Lo: 66°
Feels Like: 69°
Delphi
Scattered Clouds
67° wxIcon
Hi: 83° Lo: 66°
Feels Like: 67°
Monticello
Scattered Clouds
67° wxIcon
Hi: 82° Lo: 65°
Feels Like: 67°
Logansport
Scattered Clouds
72° wxIcon
Hi: 81° Lo: 65°
Feels Like: 72°
Some more storms ahead....
WLFI Radar
WLFI Temps
WLFI Planner

COVID-19 Important links and resources

As the spread of COVID-19, or as it's more commonly known as the coronavirus continues, this page will serve as your one-stop for the resources you need to stay informed and to keep you and your family safe. CLICK HERE

Closings related to the prevention of the COVID-19 can be found on our Closings page.

Community Events