Tuesday, November 17, 2009
Left Handed Goldfoots
My brother and I are left-handed. So is our cousin, another Goldfoot, son of our father's brother. His daughter is also left handed, so she is a 1st cousin once removed. On the other Goldfoot tree, I have learned that Norman Goldfoot was left-handed. He was the son of Louis Goldfoot, whose grandfather was also a Chaim Goldfoot. Louis and Norman lived in South Africa. The question I have is: Is this in our genes? Our parents were both right-handed.
Genetics
The role genetics may play in handedness is not clear. It is possible, common, and normal for two right-handed parents to have a left-handed child, and for two left-handed parents to have a right-handed child. Some families do seem to have more lefties than others, but the meaning of this is elusive.
About our health: However, a new study, conducted in the United Kingdom, suggests that left-handers may be a tiny bit more vulnerable than righties to certain diseases, including inflammatory bowel disease (IBD), colitis, ulcerative colitis and Crone’s disease. Nothing in the study indicates why this may be true. It’s not likely something we need to worry about.
From Wikipedia:
Hand orientation is developed in fetuses, most commonly determined by observing which hand is predominantly held close to the mouth.
In 2007, researchers discovered LRRTM1, the first gene linked to increased odds of being left-handed.
Testosterone: Exposure to higher rates of testosterone before birth can lead to a left-handed child This is the Geschwind theory, named after the neurologist who proposed it, Norman Geschwind. It suggests that variations in levels of testosterone during pregnancy shape the development of the fetal brain. Testosterone suppresses the growth of the left cerebral hemisphere and so more neurons migrate to the right hemisphere. The highly developed right hemisphere is now better suited to function as the center of language and handedness. The fetus is more likely to become left-handed, since the right hemisphere controls the left half of the body. The theory goes on to tie the exposure to higher levels of testosterone and the resultant right-hemisphere dominance to auto-immune disorders, learning disorders, dyslexia, and stuttering, as well as increased spatial ability.
We have famous lefties. Presidents were Garfield, Hoover, Truman, Ford, Reagan, Bush, Clinton and Obama. Others include Alexander the Great, Julius Caesar, Kings George II, VI, Charles, and William. Benjamin Netanyahu and Ehud Olmert are lefties. My favorites Jay Leno and Shirley MacLain are even lefties. Creative people are in the left category. We may be a minority and have been ridiculed throughout the centuries with "left" being a negative word, but we have made our mark.
Left Handed Day is coming on August 13, 2009. See http://www.lefthandersday.com/tour5.html
Reference: http://www.left-hand.org/
http://www.indiana.edu/~primate/left.html for list of famous people
Genetics
The role genetics may play in handedness is not clear. It is possible, common, and normal for two right-handed parents to have a left-handed child, and for two left-handed parents to have a right-handed child. Some families do seem to have more lefties than others, but the meaning of this is elusive.
About our health: However, a new study, conducted in the United Kingdom, suggests that left-handers may be a tiny bit more vulnerable than righties to certain diseases, including inflammatory bowel disease (IBD), colitis, ulcerative colitis and Crone’s disease. Nothing in the study indicates why this may be true. It’s not likely something we need to worry about.
From Wikipedia:
Hand orientation is developed in fetuses, most commonly determined by observing which hand is predominantly held close to the mouth.
In 2007, researchers discovered LRRTM1, the first gene linked to increased odds of being left-handed.
Testosterone: Exposure to higher rates of testosterone before birth can lead to a left-handed child This is the Geschwind theory, named after the neurologist who proposed it, Norman Geschwind. It suggests that variations in levels of testosterone during pregnancy shape the development of the fetal brain. Testosterone suppresses the growth of the left cerebral hemisphere and so more neurons migrate to the right hemisphere. The highly developed right hemisphere is now better suited to function as the center of language and handedness. The fetus is more likely to become left-handed, since the right hemisphere controls the left half of the body. The theory goes on to tie the exposure to higher levels of testosterone and the resultant right-hemisphere dominance to auto-immune disorders, learning disorders, dyslexia, and stuttering, as well as increased spatial ability.
We have famous lefties. Presidents were Garfield, Hoover, Truman, Ford, Reagan, Bush, Clinton and Obama. Others include Alexander the Great, Julius Caesar, Kings George II, VI, Charles, and William. Benjamin Netanyahu and Ehud Olmert are lefties. My favorites Jay Leno and Shirley MacLain are even lefties. Creative people are in the left category. We may be a minority and have been ridiculed throughout the centuries with "left" being a negative word, but we have made our mark.
Left Handed Day is coming on August 13, 2009. See http://www.lefthandersday.com/tour5.html
Reference: http://www.left-hand.org/
http://www.indiana.edu/~primate/left.html for list of famous people
