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Measurement of plasma phosphorylated tau 217 offers transformed paradigms for clinical trials of treatments for Alzheimer’s disease

Introduction The recent report characterising the utility of a commercially available immunoassay of phosphorylated tau 217 (p-tau217) in plasma to detect Alzheimer’s disease (AD) pathology was greeted with widespread enthusiasm (Ashton et al., 2024). The report itself, and much of the comment in response to it, focused on its potential use in clinical diagnosis: augmenting the ability to distinguish AD from other causes of dementia, to distinguish early AD from mild cognitive impairment (MCI) or to detect AD in its preclinical stages. However, the full benefit of these functions would only be realised once effective drugs to prevent AD progression became available. Here, I focus on a much more immediate application, the way that p-tau217 testing allows for the development of clinical trials which are dramatically cheaper, less demanding and shorter than those which have to date been used to assess the efficacy of proposed disease-modifying treatments for AD. Key characteristics of...
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Large, real-world study of pharmacogenetic testing to guide treatment shows it doesn't work

Pharmacogenetic testing means identifying which genetic variants a patient carries and then using that information to guide what drug treatment they should be prescribed. It's something one would think ought to be helpful. Variation in key genes might affect how drugs were metabolised or how well they worked on their molecular target. Within the field of cancer treatment there is clear evidence that genetic testing can be used to define different subtypes of cancer and that this can result in more effective treatment programs being used. There is plenty of research to show that certain commonly occurring variants will result in some drugs being metabolised more slowly, meaning that in somebody carrying one of these variants the drug may accumulate in higher concentrations, increasing the risk of side effects. Common sense would predict that testing patients and providing lower doses to such "slow metabolisers" should make them less likely to experience adverse effects and...
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Sex and gender

This post is just here because I find myself having to make the same arguments again and again on twitter so in future I'm just going to link to this. Do I know what I'm talking about? I was a psychiatrist in the National Health Service for thirty years. That means I qualified as a medical doctor and then had post-graduate training, which naturally included some material on human development and sex and gender. I also have two doctoral degrees in human genetics, an MD and a PhD, and have been an author on hundreds of peer-reviewed papers, mostly on human genetics. Because of my research in genetics I am an Honorary Professor at two different London universities. My bio is here: http://www.davecurtis.net/dcurtis.html and the publications can be viewed here: https://scholar.google.co.uk/citations?hl=en&user=Vrr4Ig0AAAAJ&view_op=list_works&sortby=pubdate Do I do research in sexual development in humans? No. Do I understand it? Yes. I've read the stuff that ...
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The "omnigenic" model for schizophrenia - why it's even worse than you think.

I'm happy to see the article by Boyle, Yang and Pritchard (Boyle et al, 2017)  getting so much attention. Quite justifiably, many people are commenting on it and I thought I would add my two pence worth. To summarise, I think the main claim they are making is that for a complex disease there will be a relatively small number of "core" genes whose functioning is related to disease mechanisms but that a very large number of polymorphisms will impact to a small extent on these core genes through gene expression networks. This then leads to a phenomenon whereby GWAS hits are very widely scattered through the genome. Most of these hits will not be anywhere near genes involved in disease mechanisms, they'll just reflect impacts on generic expression networks in one way or another. Here, I'd like to add another dimension, taking schizophrenia as an example. My claim will be that as well as the core genes there will be many other genes which do have an effect on risk,...
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2017 World Congress of Psychiatric Genetics

From: International Society of Psychiatric Genetics [ mailto:info@ispg.net ] Sent: 09 March 2017 14:34 To: Curtis, David < d.curtis@ucl.ac.uk > Subject: 2017 WCPG Registration Now Open! 2017 WORLD CONGRESS OF PSYCHIATRIC GENETICS OCTOBER 13 - 17, 2017 LOEWS SAPPHIRE FALLS RESORT ORLANDO, FLORIDA International Society of Psychiatric Genetics , 5034-A Thoroughbred Lane ,  Brentwood ,  TN 37027 From: Curtis, David [ mailto:d.curtis@ucl.ac.uk ] Sent: Thursday, March 09, 2017 11:54 AM To: Info ISPG < info@ispg.net > Subject: RE: 2017 WCPG Registration Now Open! Hi. Sorry, I won’t be coming to the USA while there is a blanket ban on visitors from certain muslim-majority countries and while people from UK seem to be arbitrarily barred on the basis of their colour and/or religion. It’s a shame because I would have liked to attend. Regards - Dave Curtis From: Info ISPG [ mailto:info@ispg.net...
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Nailing Hunt's lies

Here is the soundbite which Hunt has been repeating ad nauseam: "And at the moment we have an NHS where if you have a stroke at the weekends, you're 20% more likely to die. That can't be acceptable." Sounds quite impressive? I tweeted him to ask for evidence and got no reply so I decided to look for my own. It wasn't hard to find. I'll deal with the best and most recent example. The headline finding from this paper is that patients admitted at weekends with a stroke diagnosis have an increased 7-day mortality of 19%, apparently just as Hunt claims: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4487251/ The 7-day mortality for week-end admissions is 12.9% and for week-day admissions is 11.1% and if you factor in comorbidities etc. this gives you an adjusted mortality odds ratio of 1.19. Just as Hunt says. But let's look more closely. At some numbers buried in the text of the paper and not even given a p value, even though they are probably the most st...
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How to find a needle in a very big haystack

I have two sons. One is 25, the other 18. The 25-year-old is probably OK now. Bright and sensible, we would be extremely unlucky if serious harm were to befall him. For the younger one, though, there remains some cause for concern. Though equally bright and sensible, he is yet to live through the main age of risk for developing the most common and serious illness to affect young people. By and large they are a healthy bunch and serious illnesses are very rare. But schizophrenia is not rare at all. Upwards of half a million people in Britain will develop schizophrenia at some point, mostly between the ages of 18 and 25. I've met hundreds of them myself. And each time I do I am aware not only of the patient in front of me, suffering terrible psychotic symptoms or confused and rambling, but also of two parents who once, like me, had a lively, promising child but who now face a future as "carers" of an adult with severe mental illness. Although factors such as stress...
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