In a previous post about brain injuries in sport, I wrote about the Centre for Traumatic Encephalopathy, which collects and studies brain tissue from athletes involved in high-contact sports. Recently another "brain bank" has been in the news; the Harvard Brain Tissue Research Center at McLean Hospital, where a freezer malfunction damaged one-third of the world's largest collection of brain tissue donated for autism research.
150 brains were prematurely thawed as a result of the broken freezer, with alarm systems and daily inspections failing to alert staff to the malfunction until it was too late. Some of the tissue may still be useable for genetic research, but it's considered to be a huge setback in the field of autism research generally. Postmortem research has previously led to breakthroughs in the study of Huntingdon's disease and Parkinsons.
The loss of the potential research opportunities afforded by the collection is devastating not only to the medical community, but to the families of those whose brains were donated for research. The hospital is conducting two investigations into the fault, with a third carried out by a charity, Autism Speaks.
Showing posts with label genetics. Show all posts
Showing posts with label genetics. Show all posts
Monday, 18 June 2012
Monday, 27 February 2012
IMFW: Turned Into Bone
This week's IMFW is about an extremely rare and extremely curious genetic illness: fibrodysplasia ossificans progressiva. In this disease, fibrous tissue such as muscle, tendons and ligaments are ossified - literally turned into bone - when damaged.
As you can imagine, the illness causes severe disability, with sufferers becoming slowly trapped inside immovable sheets of bone; new growths of bone often join up with the main skeleton. Bone growths may leave patients unable to eat, speak, sit down or even breathe as the growing bones compress the lungs. Attempts to remove the excess bone usually only results in further growth, because any injury (such as surgery) to fibrous tissue is liable to result in ossification of that tissue. The notable early symptom of this illness is that babies with the genetic mutation which causes fibrodysplasia ossificans progressiva are usually born with deformed big toes; however, the illness is so rare that sufferers are often misdiagnosed, and the bone growths taken to be cancerous tumours.
One notable sufferer was Harry Eastlack, who died before his fortieth birthday and bequeathed his skeleton to medical science. You can see a photograph of it here.
Although the genetic mutation which causes this condition has been identified, there is no cure and no real treatment.
As you can imagine, the illness causes severe disability, with sufferers becoming slowly trapped inside immovable sheets of bone; new growths of bone often join up with the main skeleton. Bone growths may leave patients unable to eat, speak, sit down or even breathe as the growing bones compress the lungs. Attempts to remove the excess bone usually only results in further growth, because any injury (such as surgery) to fibrous tissue is liable to result in ossification of that tissue. The notable early symptom of this illness is that babies with the genetic mutation which causes fibrodysplasia ossificans progressiva are usually born with deformed big toes; however, the illness is so rare that sufferers are often misdiagnosed, and the bone growths taken to be cancerous tumours.
One notable sufferer was Harry Eastlack, who died before his fortieth birthday and bequeathed his skeleton to medical science. You can see a photograph of it here.
Although the genetic mutation which causes this condition has been identified, there is no cure and no real treatment.
Friday, 3 February 2012
The Silence of the Gland: Diagnosed
It's been a while since I wrote the last post about my previous attempts at diagnosis, so I decided to man up and get the heck on with it. Yeah! USA! USA!*
Obviously my tales of pituitary surgery will be the most enthralling/gross, but who knows, maybe the events leading up to surgery will also be of interest to someone. If worst comes to the worst and I develop dementia in my old age, I guess I can read all about my exciting earlier life!
It had been determined that there was nothing wrong with my heart. My cardiologist ordered several blood tests and referred me to endocrinology.
This is where it gets dull and technical.
What I didn't know was that, up until that point, although I showed symptoms of hyperthyroidism, my doctors had only ordered blood tests which looked at my levels of thyroid-stimulating hormone, rather than the thyroid hormones themselves. TSH is produced by the pituitary, then it travels through the blood and spurs the thyroid gland to produce thyroid hormones. Usually, when hyperthyroidism is caused by a problem with the thyroid gland, you would expect the pituitary gland to produce only very low level of thyroid-stimulating hormone (TSH), as the body is trying to suppress the overproduction of thyroid hormones. However, my TSH tests had always come back within the "normal range", so it was assumed that hyperthyroidism was not the problem.
Then a letter dropped through my door from one of the consultant endocrinologists at the hospital. It informed me that my blood test results were "very unusual", and that they suspected I may have a rare condition called resistance to thyroid hormone (RTH). I was called into the hospital for further tests.
At the hospital, I met the consultant who had written the letter. To this day, he possesses one of the finest moustaches I have ever seen. Whilst I sat wondering what kind of scissors he used to trim it so neatly across his upper lip, he informed me that resistance to thyroid hormone is a rare genetic condition, in which most or all of the body's tissues do not respond normally to thyroid hormone. In some people, there are few symptoms as the whole body is equally resistant to the hormone, resulting in high levels of thyroid hormone in the blood but few issues associated with this; in others, the pituitary is more resistant than other tissues to thyroid hormone, leading to some symptoms of hyperthyroidism.
My blood tests showed that I had normal levels of thyroid stimulating hormone, but high levels of thyroid hormones T3 and T4 in my blood - indicating that my pituitary was not responding normally to the high thyroid levels. I was told that the only other possibility was that I might have a tumour on my pituitary which was producing TSH, a.k.a. a TSH-oma, but that this was even more absurdly rare than resistance to thyroid hormone and it was much more likely to be RTH.
I had more complex blood tests at the hospital, and they even took DNA samples to look for the particular mutation. Everything came back negative. The moustachioed doctor's main area of interest was resistance to thyroid hormone, so he passed my case to a colleague specialising in pituitary issues; it was pretty much certain by then that I had a pituitary adenoma, they just needed an MRI to show the tumour. Which they did - and I've already written a post about the MRI, which you can read here.
I don't really remember the phone call from my endocrinologist informing me that I did indeed have a pituitary macroadenoma, measuring 23mm by 19mm by some other measurement which I've forgotten. By that point I had had a chance to get used to the idea that I had a pituitary tumour, so the phone call was really just official confirmation with additional details. But I do remember calling my mum to tell her the news; I walked home from work the long way, through one of the big parks nearby.
After that it was a bit of a whirl of activity. I got the news just before Christmas 2010 and as soon as I arrived back in town after New Year's, I had to arrange to start lanreotide injections to reduce the amount of TSH the tumour was producing. They wanted me to have injections for three months, then a transsphenoidal hypophysectomy (that's pituitary surgery to you and me) immediately afterwards. I had to spend a day in hospital so that they could check that my pituitary was still producing other hormones at a normal level and wasn't about to collapse due to a lack of adrenocorticotropic hormone or something. It all passed in a bit of a blur; the idea of surgery was definitely what most occupied my mind in the intervening months...
UPDATE: You can click here to read about my experience having an MRI scan, or click here to go back and read about my earlier experiences trying to get a diagnosis.
____________________________________________________________
*Or something...
Obviously my tales of pituitary surgery will be the most enthralling/gross, but who knows, maybe the events leading up to surgery will also be of interest to someone. If worst comes to the worst and I develop dementia in my old age, I guess I can read all about my exciting earlier life!
LAST TIME ON PITUITARY ADEMOANER:
This is where it gets dull and technical.
What I didn't know was that, up until that point, although I showed symptoms of hyperthyroidism, my doctors had only ordered blood tests which looked at my levels of thyroid-stimulating hormone, rather than the thyroid hormones themselves. TSH is produced by the pituitary, then it travels through the blood and spurs the thyroid gland to produce thyroid hormones. Usually, when hyperthyroidism is caused by a problem with the thyroid gland, you would expect the pituitary gland to produce only very low level of thyroid-stimulating hormone (TSH), as the body is trying to suppress the overproduction of thyroid hormones. However, my TSH tests had always come back within the "normal range", so it was assumed that hyperthyroidism was not the problem.
Then a letter dropped through my door from one of the consultant endocrinologists at the hospital. It informed me that my blood test results were "very unusual", and that they suspected I may have a rare condition called resistance to thyroid hormone (RTH). I was called into the hospital for further tests.
At the hospital, I met the consultant who had written the letter. To this day, he possesses one of the finest moustaches I have ever seen. Whilst I sat wondering what kind of scissors he used to trim it so neatly across his upper lip, he informed me that resistance to thyroid hormone is a rare genetic condition, in which most or all of the body's tissues do not respond normally to thyroid hormone. In some people, there are few symptoms as the whole body is equally resistant to the hormone, resulting in high levels of thyroid hormone in the blood but few issues associated with this; in others, the pituitary is more resistant than other tissues to thyroid hormone, leading to some symptoms of hyperthyroidism.
My blood tests showed that I had normal levels of thyroid stimulating hormone, but high levels of thyroid hormones T3 and T4 in my blood - indicating that my pituitary was not responding normally to the high thyroid levels. I was told that the only other possibility was that I might have a tumour on my pituitary which was producing TSH, a.k.a. a TSH-oma, but that this was even more absurdly rare than resistance to thyroid hormone and it was much more likely to be RTH.
I had more complex blood tests at the hospital, and they even took DNA samples to look for the particular mutation. Everything came back negative. The moustachioed doctor's main area of interest was resistance to thyroid hormone, so he passed my case to a colleague specialising in pituitary issues; it was pretty much certain by then that I had a pituitary adenoma, they just needed an MRI to show the tumour. Which they did - and I've already written a post about the MRI, which you can read here.
I don't really remember the phone call from my endocrinologist informing me that I did indeed have a pituitary macroadenoma, measuring 23mm by 19mm by some other measurement which I've forgotten. By that point I had had a chance to get used to the idea that I had a pituitary tumour, so the phone call was really just official confirmation with additional details. But I do remember calling my mum to tell her the news; I walked home from work the long way, through one of the big parks nearby.
After that it was a bit of a whirl of activity. I got the news just before Christmas 2010 and as soon as I arrived back in town after New Year's, I had to arrange to start lanreotide injections to reduce the amount of TSH the tumour was producing. They wanted me to have injections for three months, then a transsphenoidal hypophysectomy (that's pituitary surgery to you and me) immediately afterwards. I had to spend a day in hospital so that they could check that my pituitary was still producing other hormones at a normal level and wasn't about to collapse due to a lack of adrenocorticotropic hormone or something. It all passed in a bit of a blur; the idea of surgery was definitely what most occupied my mind in the intervening months...
UPDATE: You can click here to read about my experience having an MRI scan, or click here to go back and read about my earlier experiences trying to get a diagnosis.
____________________________________________________________
*Or something...
Monday, 2 January 2012
IMFW: Moral Dilemma
The first Interesting Medical Fact of the Week for 2012 - the first interesting fact for a whole new year - concerns something (or rather, someone) that I've written about before. Highly relevant to the pituitary adenoma theme of this blog, in fact.
In my last post, I mentioned Charles Byrne, the Irish Giant, as he was known in his lifetime, a man who suffered from acromegaly in the 1780s. He was briefly a popular attraction in London before succumbing to alcoholism and dying very young at the age of 22. Although he is probably the most well known, as his skeleton is part of the collection in the Hunterian Museum, there were several well-known Irish giants, all of whom likely suffered from acromegaly, who exhibited themself across Europe at the time.
Byrne's skeleton was preserved against his will; the story goes that he was so keen to avoid his body falling into the clutches of John Hunter, a noted surgeon of the time, that his will requested his friends bury his body at sea in a lead coffin. Hunter managed to get his hands on the body, however, allegedly through bribery.
It's curious how many websites I've found when googling the name "Charles Byrne" which not only fail to mention acromegaly, but fail to mention that Byrne had an illness at all - as though growing to 7'7" is a kind of character flaw which could happen to anybody. His skeleton is still on display to the public at the Hunterian Museum, and around a year ago there was some publicity around some genetic research that has been taking place, looking at a genetic cause for pituitary tumours which recur in families, which identified some modern-day acromegaly patients who may be related to Byrne.
More on that research another day.
Today, the news is that there have been calls for Charles Byrne's skeleton to be removed from display, and buried in accordance with his original wishes. It seems fairly unlikely that this will happen, he's a significant feature of the museum; but it's an interesting debate, and on the whole, I have to say that I would broadly be in favour of allowing him to be buried. It's interesting that the moral debate is still going on, more than two hundred years after his death.
In my last post, I mentioned Charles Byrne, the Irish Giant, as he was known in his lifetime, a man who suffered from acromegaly in the 1780s. He was briefly a popular attraction in London before succumbing to alcoholism and dying very young at the age of 22. Although he is probably the most well known, as his skeleton is part of the collection in the Hunterian Museum, there were several well-known Irish giants, all of whom likely suffered from acromegaly, who exhibited themself across Europe at the time.
Byrne's skeleton was preserved against his will; the story goes that he was so keen to avoid his body falling into the clutches of John Hunter, a noted surgeon of the time, that his will requested his friends bury his body at sea in a lead coffin. Hunter managed to get his hands on the body, however, allegedly through bribery.
It's curious how many websites I've found when googling the name "Charles Byrne" which not only fail to mention acromegaly, but fail to mention that Byrne had an illness at all - as though growing to 7'7" is a kind of character flaw which could happen to anybody. His skeleton is still on display to the public at the Hunterian Museum, and around a year ago there was some publicity around some genetic research that has been taking place, looking at a genetic cause for pituitary tumours which recur in families, which identified some modern-day acromegaly patients who may be related to Byrne.
More on that research another day.
Today, the news is that there have been calls for Charles Byrne's skeleton to be removed from display, and buried in accordance with his original wishes. It seems fairly unlikely that this will happen, he's a significant feature of the museum; but it's an interesting debate, and on the whole, I have to say that I would broadly be in favour of allowing him to be buried. It's interesting that the moral debate is still going on, more than two hundred years after his death.
Monday, 21 November 2011
IMFW: Retrospective Justification
When I was a child, I hated sprouts.
No, wait - let me rephrase that:
I hate sprouts.
I have always hated them. I intend to continue hating them until I'm so old that my tastebuds have shrivelled up entirely beyond use - and after that I will still refuse to eat them, on principle. As a child, I was often served a Token Brussels Sprout at Sunday Dinner, which I had to eat if I wanted to get any pudding. And, as I always wanted pudding, I used to attempt to chop the sprout into as few pieces as possible and then swallow them whole, like a self-loathing vegan snake.
For years, I suffered this horror almost every week and was told off for my fussy eating habits. But now, it has been revealed that the hatred of brussels sprouts is, in fact, genetic. Or at least, probably genetic. Those people who have this gene can taste the bitter and hideous taste of a chemical called phenylthiocarbamide, which is extremely similar to a chemical found in brassicas, like brussels sprouts. And cabbage, broccoli, cauliflower... pretty much all the vegetables I and so many other sensible people hate.
Now, I've seen different theories suggested for why some people like sprouts and others can't stand them - but this is definitely my favourite. Because it means that all children everywhere, when faced with a plate of sprouts, can now scowl up at their parents and say: it's your fault I don't like them.
No, wait - let me rephrase that:
I hate sprouts.
I have always hated them. I intend to continue hating them until I'm so old that my tastebuds have shrivelled up entirely beyond use - and after that I will still refuse to eat them, on principle. As a child, I was often served a Token Brussels Sprout at Sunday Dinner, which I had to eat if I wanted to get any pudding. And, as I always wanted pudding, I used to attempt to chop the sprout into as few pieces as possible and then swallow them whole, like a self-loathing vegan snake.
For years, I suffered this horror almost every week and was told off for my fussy eating habits. But now, it has been revealed that the hatred of brussels sprouts is, in fact, genetic. Or at least, probably genetic. Those people who have this gene can taste the bitter and hideous taste of a chemical called phenylthiocarbamide, which is extremely similar to a chemical found in brassicas, like brussels sprouts. And cabbage, broccoli, cauliflower... pretty much all the vegetables I and so many other sensible people hate.
Now, I've seen different theories suggested for why some people like sprouts and others can't stand them - but this is definitely my favourite. Because it means that all children everywhere, when faced with a plate of sprouts, can now scowl up at their parents and say: it's your fault I don't like them.
Monday, 31 October 2011
IMFW: Hedgehogs
Given the runaway success of my previous post about British spies wanting to sneak hormones into Hitler's food,* I have decided to attempt a regular weekly post about interesting medical or medicine-related facts. I have, you'll be pleased to know, imaginatively decided to call this series the Interesting Medical Fact of the Week, or IMFW for short.
Anyone who knows me well can tell you that I love hedgehogs greatly, and if I actually owned a house and could look after it properly, I would have one of my very own. It occurs to me that responsible pet ownership is probably one of the dread Seven Signs of Adulthood; when I was little, I would have happily housed a pony in the bathroom - if only my parents had bought me one. Damn them.
Anyway, as it turns out, I'm not just rambling incoherently about hedgehogs for no reason! Because the topic of this week's IMFW is the sonic hedgehog gene, a.k.a. SHH. If you ever want to send it mail, you can find it at chromosome 7, where it snuffles around in bars and punches anyone who calls it a rat.
I first heard of the sonic hedgehog gene in my first year at university, from friends who were studying medicine, and (not unreasonably) I initially believed that they were pulling my leg about its name. As it turns out, I should have had more faith in the doctors of the future. Its name originates from the fact that, when researchers created fruit fly embryos which lacked this and other similar genes, the embryos grew spiny protuberances. Apparently, researchers are always doing this kind of thing to fruit flies. Not out of scientific interest, you understand - they're just sick in the head.**
The sonic hedgehog gene (and its woodland genetics counterparts, the indian hedgehog gene and desert hedgehog gene) are cunning beasts, no doubt, but if you want a detailed description of what they do then you can head to wikipedia. Or simply grab a first year medical student and shake them repeatedly. Essentially, SHH is important in the development of embryos, as it codes for a protein which helps to signal the layout of bodyparts.
What I find particularly interesting is the debate around its name; a couple of years ago I listened to an interesting program on Radio 4*** which looked at the naming conventions in genetics, and lighted on the sonic hedgehog gene as a particularly good example of the fact that a name bestowed on a gene in the lab might seem hilarious in the light of certain spiny protuberances, but will sound rather less funny to the parents being told that their child has a serious disability because of a mutation in his or her sonic hedgehog gene.
_______________________________________________________________________
*Yes, you heard me - a whopping seven or so people read it. Crikey.
**Like me! :D
***Old before my time? Moi?
Anyone who knows me well can tell you that I love hedgehogs greatly, and if I actually owned a house and could look after it properly, I would have one of my very own. It occurs to me that responsible pet ownership is probably one of the dread Seven Signs of Adulthood; when I was little, I would have happily housed a pony in the bathroom - if only my parents had bought me one. Damn them.
Anyway, as it turns out, I'm not just rambling incoherently about hedgehogs for no reason! Because the topic of this week's IMFW is the sonic hedgehog gene, a.k.a. SHH. If you ever want to send it mail, you can find it at chromosome 7, where it snuffles around in bars and punches anyone who calls it a rat.
I first heard of the sonic hedgehog gene in my first year at university, from friends who were studying medicine, and (not unreasonably) I initially believed that they were pulling my leg about its name. As it turns out, I should have had more faith in the doctors of the future. Its name originates from the fact that, when researchers created fruit fly embryos which lacked this and other similar genes, the embryos grew spiny protuberances. Apparently, researchers are always doing this kind of thing to fruit flies. Not out of scientific interest, you understand - they're just sick in the head.**
The sonic hedgehog gene (and its woodland genetics counterparts, the indian hedgehog gene and desert hedgehog gene) are cunning beasts, no doubt, but if you want a detailed description of what they do then you can head to wikipedia. Or simply grab a first year medical student and shake them repeatedly. Essentially, SHH is important in the development of embryos, as it codes for a protein which helps to signal the layout of bodyparts.
What I find particularly interesting is the debate around its name; a couple of years ago I listened to an interesting program on Radio 4*** which looked at the naming conventions in genetics, and lighted on the sonic hedgehog gene as a particularly good example of the fact that a name bestowed on a gene in the lab might seem hilarious in the light of certain spiny protuberances, but will sound rather less funny to the parents being told that their child has a serious disability because of a mutation in his or her sonic hedgehog gene.
 |
| A hedgehog, though not an obviously sonic one. |
*Yes, you heard me - a whopping seven or so people read it. Crikey.
**Like me! :D
***Old before my time? Moi?
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