Today's post is taken from the New York Times.
Handedness clearly runs in families. The 2007 paper by the group at Oxford identified a gene, LRRTM1, that they discovered in the course of studying children with dyslexia, and which turned out to be associated with the development of left-handedness.
Dr. Francks, who is now at the Max Planck Institute for Psycholinguistics in the Netherlands, recalls that the discovery made headlines and attracted a great deal of attention, the more so because this gene was also found disproportionately in people with schizophrenia, even though none of these connections are simple or well understood. “We’re not looking for a gene for handedness or a gene for schizophrenia,” he said. “We’re looking for subtle relationships.” The gene affects the ways that neurons communicate with one another, he said, but its mechanisms still need to be studied
I was the only person growing up in my family who is left handed (and immune compromised.) One of my sister's is right handed and dyslexic, or, I suppose I should say "has a diagnosis of dyslexia." Chris is right-handed. Our middle son, Alex, is left-handed. All of my husband's immediate family is right handed. The New York Times article deserves a read, but it doesn't add anything new to schizophrenia, that forever illusive "organic brain dysfunction" which tantalizing is linked to just about everything in life that involves being human.
None of it turns out to be simple. The idea of links to schizophrenia has been particularly persistent, but schizophrenia is a complicated and probably heterogeneous disorder, and studies of different populations show different patterns; last year, a study found no increased risk with non-right-handedness for schizophrenia or poorer neurocognition.
On the Left Hand, There Are No Easy Answers, Perry Klass, MD, March 6, 2011