What is the chance of having a left-handed child?
Answer: Although no definite gene has been determined to cause lefthandedness it does seem to run quite strongly in families. It is not predictable based on the handedness of parents and grandparents in the same way as eye colour but the handedness of the parents does seem to be a significant overall factor in determining the handedness of the children.
As an overall average, the percentages are something like this:
Two right handed parents, 9%
Left handed father, 12%
Left handed mother, 16%
Two left handed parents, 20%
Some interesting figures come out of these statistics:
- More than 50% of left-handers do not know of any other left-hander anywhere in their living family.
- Around 75% of left-handers have two right-handed parents and only 2% have two left-handed parents.
- Between 7 and 8 out of 10 children born to two left handed parent will be right handed.
Of course, the chances of having a left-hander in the family increase the more children you have. So there is still hope for right-handed parents – if you have enough children, you may still be lucky enough to have a left-hander!
You can read Keith’s more detailed article about this here
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Interesting subject. Prof Robert Winston (I think thats his surname anyway – he one whos always on the teli) has his own theory. He claims that in a set of identifcal twins 1 is left handed and the other is right handed. This is because when in the womb, and the egg splits to form 2 babies, they are the mirror image of each other hence the different ‘handed-ness’. There is also evidence that sometimes the female body will stop developing one of the babies and this just seems to fade away, its like a bodies way of saying it only wants to produce 1 baby, not 2. When ths happens you can be left with just the left handed baby.
I’m an only child, left handed and all relatives are right handed. Maybe at a very early age in the womb I had a twin which didn’t develop any further!!! Interesting hey?
Also, my dad is right handed but he ties his shoe laces and deals cards left handed. In turn, his dad is also right handed but feels that he should have been a lefty but when he was young lefties were discouraged and you had to write with your right hand!
I’ve now married a ‘righty’ and our 2 kids are both right handed. So it appears I’m unique in our family (or as my mum would say, unique in more than 1 way)!!!!
Well, i’m an identical twin and my sister is right-handed, so are both my parents and everything. The theory i was told is that we got held on the same side all the time so my right arm got smushed or something.