The fascination of left-handed people

Left-handers, a decried but fascinating minority

Research into left-handedness is well under way. Many animals are analysed and questioned (they are not very forthcoming), and humans are not to be outdone. However, why and how we are born left- or right-handed remains a mystery and will remain so for a long time to come: we are not yet ready to reveal all our secrets.

What does science have to say?

Genetic or not genetic? Environmental or cultural? As soon as a lead is judged to be serious, it is finally shot down by new results. Recent studies published in Nature Communications have found a new lead that points to a family of proteins called tubulins, which are thought to play an important role in the development of laterality in the brain. The TUBB4B gene (well, you don’t have to remember everything, but there may be a check at the end!) is 2.7 times more likely to contain rare coding variants in left-handed people. But not in all left-handers, so we’re back to square one…

Other researchers, published in the journal eLife, are trying to demonstrate (it’s their job after all :)) that asymmetries exist in the spinal cord. These asymmetries would also be influenced by the uterine environment – in any case, it’s always the mother’s fault. Some researchers have been able to isolate and identify four genetic regions associated with left-handedness, three of which are linked to proteins that influence brain structure. The study of these famous genetic markers in the brains of left-handers showed differences in the white matter, the long nerve fibres that enable areas of the brain to communicate. I still don’t know whether the left-handers analysed were dead or alive, and if they were no longer alive, how did they manage to communicate?

In short, we don’t know very much, but what are we looking for?

What do right-handers have to say?

Some people think we’re clumsier, or even downright left-handed; my mother-in-law thinks we’re almost cursed, while others are a little jealous. One of my dear friends told me that she’d developed a bit of a complex: she was a photographer and right-handed, but she wished she were left-handed because we’re seen as ‘more creative’. That’s right, we left-handers have our own top 150, including the dead, the living, those who never existed, those suspected of being left-handed, proven left-handers and those who aren’t left-handed at all, and we swear we’d have put our left hand up to it!