Dr Pietro Fratta completed his first MRC-MND Association Clinical Research Training Fellowship in 2014. Last year he was awarded a new £1.16 million Clinician Scientist Fellowship to continue his research at University College London, studying the earliest physical changes that affect motor neurons in MND (our reference 946-795). Our contribution to this four year research fellowship is £280,000.
As his first Fellowship progressed, Dr Fratta became more interested in the field of RNA biology, where he is rapidly establishing himself as an expert. His latest project aims to see whether RNA plays a pivotal role in the earliest signs of cellular damage that occur in MND.
RNA is the cell’s copy of our genetic material known as DNA; Dr Fratta is hoping to establish if the transport of RNA molecules along the nerve fibres is impaired and if so, whether there are particular versions of RNA that are particularly important for motor neurone health and survival.
Several lab studies have shown that the process of transporting things up and down the motor neurones is impaired long before the physical signs of damage are seen. His research will seek to find out what RNA molecules are present in both the cell body of the motor neuron and the nerve fibres.Read More »
Did you know the MND Association also supports people who have Kennedy’s disease?
In May a new clinic specialising in Kennedy’s disease opened in London at the National Hospital for Neurology and Neurosurgery.
To mark this big step in helping support and treat people with Kennedy’s disease, Katy Styles who campaigns on behalf of the Association, and whose husband Mark has Kennedy’s disease, thought it would be a great opportunity to raise awareness of this rare condition.
Katy and Mark Styles
“There is very low awareness of this disease amongst neurologists, healthcare professionals, the general public and within the Association itself. We do all we can to explain to everybody what Kennedy’s disease is and what it’s like to live with.
“Due to the rarity of Kennedy’s disease you can feel very much alone. It is so great to be part of the MND family and the Association is key to this by making us feel part of a wider community.”
What is Kennedy’s disease?
Kennedy’s disease is a condition similar to motor neurone disease (MND) which affects motor neurones. It is sometimes called spinal and bulbar muscular atrophy (SBMA).Read More »
Dr Pietro Fratta (University College London) received his initial Training Fellowship through the MND Association/ Medical Research Council (MRC) Lady Edith Wolfson Programme in 2010. Starting on 1 February 2015, Dr Fratta was awarded a Clinician Scientist Fellowship to continue his research into MND.
Totalling £1.16 million, of which the Association has committed to contribute £280,000, this new fellowship will allow Dr Fratta to find out what RNA molecules are present in both the cell body of the motor neuron, and the nerve fibres. Read More »
Boxing day is here, there’s still some leftover turkey but let’s not forget… it’s the second day of Christmas!
“On the second day of Christmas MND research gives to you… TWO new inherited MND genes”
2014 saw the discovery of two inherited MND genes, the first being MATR3 in March and the second being TUBA4A in October. We will be discussing TUBA4A in a later blog post, but for now, here’s what we know about MATR3:
The MATR3 inherited MND gene discovery has provided us with further evidence that abnormal RNA processing is involved in MND.
The MATR3 protein, which is produced from the MATR3 gene, is commonly found in the nucleus or ‘control centre’ of the cell and is involved in the processing of RNA (the cell’s copy of DNA that is responsible for making new proteins). RNA processing has been previously associated with other inherited MND gene mutations (eg TARDBP and FUS). The MATR3 mutation also affects this process, adding more evidence to the role of abnormal RNA processing in MND.
Following on from our ’year of hope’ appeal last month an international team of researchers, including two funded by the MND Association, have identified mutations in the Matrin 3 (MATR3) gene as a cause of the rare inherited form of MND.
Inherited MND is a rare form of MND (5-10% of total MND cases) and the MATR3 gene is the latest to be identified. This rare form of MND is characterised by a family history of MND.
New gene, new gene
When a new gene is first identified this creates a great deal of ‘buzz’ amongst the MND research community, often generating more questions than answers:
How common is this inherited MND gene?
How does this gene cause MND?
This is the starting point for MATR3. Unfortunately, we just don’t know the answers to these questions at the moment. Hopefully MND researchers will now use the discovery of MATR3 to find the answers to these questions and further our understanding of this gene.
A characteristic sign of motor neurones affected by motor neurone disease is the clumps of protein visible down a microscope. Although these proteins have been observed in motor neurones from people affected by MND since the earliest descriptions in the 1870s, a key discovery was made when the identity of a protein, common to all types of MND, was unveiled as ‘TDP43’ in 2008.
Two years later a second protein called FUS was also been found to be common to all types of MND. More information on this aspect of MND can be found in an article on our research blog.
One of the exciting things about these two discoveries was that they were both linked to a set of biological pathways, known as RNA processing. The was the first major clue that RNA processing was involved in MND. When the discovery of genetic defect in the C9orf72 gene came along in 2011, that made a third MND-causing gene defect that linked to RNA processing.
The first session of the 24th International Symposium on ALS/MND after lunch yesterday was dedicated to the topic of RNA processing and dysregulation. Several of the talks presented work on understanding the role of TDP43 in MND.
There’s a scene in the 1969 film Battle of Britain where Laurence Olivier, who plays the Air Chief Marshal, is in a meeting with his two Vice Marshals. One of them complains that they don’t have enough planes; the other is more concerned with keeping the airfields working. Olivier silences them both by telling them that the fight will be won or lost on one key factor – the number of trained pilots.
It’s a rather cheesy film, but I used that story earlier this month to illustrate the importance of investing in bringing through the next generation of researchers in our battle to defeat MND. We organised a ‘get together’ of our Lady Edith Wolfson Clinical Fellows at the Sheffield Institute for Translational Neuroscience (SITraN) to share their research findings with the donor who has so generously supported the scheme. The ‘get together’ also provided a wonderful opportunity for them to exchange information and expertise with each other, as well as all the staff of SITraN, who over the course of the day were frequently shuttling between the lecture room and their labs.
The Fellowships are aimed at attracting and training the brightest and the best Clinician-Scientists (or ‘Doctor-Doctors’ as I sometimes call them – with both a medical degree and a science PhD). Even so, I couldn’t resist using this cartoon in my introduction, although the reality is very different for our Fellows – the bar is set very high and even applicants for the Junior Fellowships need to have considerable research experience and be fully ‘lab tested’.
Our host for the day was one of the world’s most respected MND ‘Doctor-Doctors’, SITraN Director Prof Pam Shaw, who welcomed everyone to the meeting and provided an overview of the multidisciplinary expertise and collaborative philosophy that underpins SITraN. Prof Shaw also has a great belief in the importance of nurturing the next generation of talent and it is no surprise that almost half of the Clinical Fellows in the programme are based at SITraN.
Are fit and active people more likely to develop MND?
Our first research presentation was from Dr Ceryl Harwood (Sheffield) who is carrying out research on the epidemiology of MND. Specifically, she is addressing the question of whether physical activity is a risk factor for MND. As she explained, this has been a long standing theory, showing us a quote from a medical journal written over 50 years ago which stated:
”Nothing has been said about the possible role in aetiology of a previous habit of athleticism. I have the uncomfortable feeling that a past history of unnecessary muscular movement carried out for no obvious reason may be followed in later life by the development of motor neurone disease in a statistically significant number of cases”
She outlined the plausibility that physical activity may contribute to a complex interplay between biological and genetic processes that may predispose an individual to develop the disease. Generating the evidence, however, is no easy matter, but she has developed and validated a novel questionnaire to measure physical history in adulthood, using data from a diabetes study in the 1990s where over 1,000 people had detailed measures taken of their actual energy expenditure.
A hundred of these participants have recently agreed to undergo rigorous face-to-face interviews and their responses were correlated with actual physical measures from over 15 years previously. In other words, she can now assess how accurately peoples’ recollection of their physical activity – both day to day work and vigorous exercise – links with their actual energy expenditure at the time. This questionnaire is now being used to compare the physical activity profiles in up to 350 people with MND and 700 control participants in Yorkshire and surrounding counties.
Should the results support the theory that physical activity is a predisposing factor in MND, she will be perfectly placed to delve into the genetic factors that underpin the selective vulnerability of motor neurons.
Repetition is bad….
Next up to the lectern was Dr Pietro Fratta, (University College London) who has been immersing himself in the mysteries of how the C9orf72 gene can cause neurodegeneration – especially MND and a related condition called Frontotemporal Dementia (FTD).
Like a needle on a vinyl record can sometimes stick and repeat the same fragment of music again and again, this gene sometimes carries a repeat in its genetic code – specifically with the letters GGGGCC occurring again and again. Dr Fratta has examined many DNA samples from MND and FTD patients and finds that these ‘repeat expansions’ are very large indeed, occurring between 700 and 4000 times!
The process through which these repeat expansions cause nerves to die is still a mystery, but Dr Fratta showed results from his lab which suggests that rather than losing its normal function, the C9orf72 gene gains some additional activity, turning it into a ‘rogue’ gene. He and his colleagues have recently shown that the repeat expansions can lead to the formation of very stable chemical structures called G-quadruplexes that have been implicated in causing nerve damage in other disorders.
He is currently studying how these structures interact with other cellular components, interfering with normal neuronal function. He is also starting to look at possible therapeutic approaches in a collaboration with the UCL School of Pharmacy to develop compounds that will bind to and hopefully inactivate these structures.
Over lunch, we were given a guided tour of the superb SITraN labs by Prof Shaw. Although I strongly believe that research is only as good as the researchers doing the work, there’s no doubt that having a purpose built institute filled with state-of-the art technology certainly doesn’t do any harm!
Then it was back into the lecture room for our afternoon presenters.
A Sheffield double act
The post-lunch session was kicked off by Dr Robin Highley, a neuropathologist who has recently completed his Fellowship and now divides his time equally between pathology duties and MND research. Dr Highley’s area of expertise is in how neurons edit the genetic instructions into precise ‘blueprints’ to make proteins, the essential building blocks of every cell in our body.
He used an entertaining analogy of making dresses form a pattern to describe the process of how DNA is made into RNA copies which can be ‘tailored’ into slightly different protein designs (to find out more about how DNA makes RNA and subsequently proteins see our earlier blog post).
Using a variety of approaches he has looked at gene expression (which genes are being switched on and off) and gene splicing (how the RNA copies are edited) patterns in both inherited and non-inherited MND, as well as in non-MND states. He finds changes occurring in thousands of genes, but by performing searches on databases of the ‘function’ of each gene he can then sort them into different groups (which are then involved in key cellular processes). This provides important clues as to which cellular pathways are altered in MND, which will help researchers around the world to focus their attention on the most common changes and hopefully start addressing the question of how these may be slowed or stopped.
Dr Highley focused his talk mainly on the TDP-43 and SOD1 forms of inherited MND, with his colleague and fellow ‘Fellow’(!) Dr Johnathan Cooper-Knock, concentrating on the C9orf72 form (the most common cause of inherited MND). Through the MND Association’s DNA Bank he has been able to obtain a large number of cell lines from patients with C9orf72 MND, along with detailed clinical information, which will allow him to compare patterns between those with fast progressing and those with more slowly progressing disease.
Although at a much earlier stage in his research, having started only 6 months ago, Dr Cooper-Knock has already identified some specific gene expression effects that may be distinct to the C9orf72 form of the disease. For more details about Dr Cooper-Knock’s work see our earlier blog post about his fellowship.
BioMOx and beyond
It was fitting that Dr Martin Turner (Oxford) gave the closing presentation. Not only was Dr Turner the first recipient of a Lady Edith Wolfson Fellowship, but he has recently been awarded a new five-year Senior Clinical Fellowship through the programme – these are highly prestigious awards, with only one in seven applicants successful.
Titling his talk ‘BioMOx and beyond’ Dr Turner outlined the challenge of identifying a specific signature of MND. He showed that whilst there is unlikely to be a single test for MND, a combination of tests (involving brain scanning and eye tracking techniques together with chemical analysis of blood, urine or cerebrospinal fluid) are showing some promise in aiding and speeding up the diagnosis, as well as predicting how the disease is likely to progress within an individual.
He highlighted the importance of international collaboration, such as the new formal link with Dr Mike Benatar in Miami, who for several years has been studying people at risk of developing inherited MND. Indeed, Dr Turner apologised for missing the morning speakers at Sheffield as he had been busy with one of Dr Benatar’s study participants in his MRI scanner at Oxford!
On the subject of international collaboration, our most recent Clinical Fellow, Dr Jemeen Sreedharan, was unfortunately unable to attend as the first two years of his Fellowship is based at the University of Massachusetts, returning to the University of Cambridge to complete his research. We look forward to having him at the next Fellows get-together!
Results from a phase I clinical trial of a drug known as ISIS 333611 have been published open-access online in the scientific journal Lancet Neurology on 29 March 2013.
This is the first time researchers have tested the effects of delivering an antisense oligonucleotide directly into the human cerebral spinal fluid (the fluid between the spinal cord) showing that it is both safe and well tolerated in people with the SOD1 form of inherited MND. For information on inherited MND please see our website.
This work suggests that this ‘antisense’ approach may be a good strategy for other neurological disorders.
What is antisense?
Antisense is a type of therapy that causes the ISIS 333611 to directly interfere with the faulty instructions for making a SOD1 protein, thus stopping the production of the disease-causing substance. This is called ‘gene silencing’ as that part of the gene is not ‘heard’ when the final protein is made.
ISIS 333611 works by targeting mRNA, the ‘messenger’ that carries the genetic instructions from the SOD1 gene to the protein-making machinery (for more about mRNA and how proteins are made see our earlier blog post). Instructions in the mRNA for making the SOD1 protein (sometimes called a ‘sense’ sequence) are faulty in people with SOD1 inherited MND, which leads to harmful SOD1 proteins being made.
So if the levels of harmful SOD1 can be reduced, might this be protective? That’s the thinking behind the treatment. By binding to the SOD1 mRNA, ISIS 333611 prevents the production of a harmful SOD1 protein. Indeed, studies in SOD1 positive animal models indicated that reducing the level of SOD1 by antisense therapy increased lifespan. However, targeting the SOD1 gene in this way is a very ‘personalised’ treatment strategy – if it does work it will only work for people who have the SOD1 from of MND.
Results from the trial
Based on the encouraging animal studies, the researchers and ISIS Pharmaceuticals conducted a phase I trial of the antisense oligonucleotide ISIS 333611.
Twenty-one people with SOD1 MND were involved in the study and results from the trial have shown that there were no toxic effects due to increased dosing of the drug and that the drug was safe and well tolerated.
In animal models antisense therapy is found to spread well throughout the central nervous system (brain and spine). However, unlike animal models, the researchers showed that concentrations of ISIS 333611 were lower in the upper end of the spinal cord and brain compared to the injection site. Due to this the delivery site of the drug will probably need to be revisited in future trials.
As this was only a short-term ‘Phase I’ trial it was not designed to test whether this antisense therapy had an effect on MND. This would only be seen with long term treatment and future trials. However, the results are encouraging as they show that this type of therapy is both safe and well tolerated in people with SOD1 MND.
Results make sense
Dr Pietro Fratta (University College London), who is a recipient of a Medical Research Council/MND Association’s Lady Edith Wolfson Clinical Research Fellowship, has written an accompanying commentary on the paper. He said that this study “paves the way for applying antisense oligonucleotides to other forms of genetically determined MND” such as the C9orf72 form of the disease.
However, he stressed that “many hurdles still need to be overcome to bring this treatment to the clinic”.Dr Fratta also cautioned that the longer-term implications of lowering SOD1 protein levels had to be examined. The antisense approach not only targets the harmful mutated SOD1 protein, but will also lower levels of ‘healthy’ normally functioning SOD1, which plays an important role in protecting neurons from damage. So, the antisense treatment approach may be a ‘double-edged sword’ that will require very careful handling.
Miller, T. M. et al. An antisense oligonucleotide against SOD1 delivered intrathecally for patients with SOD1 familial amyotrophic lateral sclerosis: a phase 1, randomised, first-in-man study. Lancet Neurology 2013 DOI: 10.1016/s1474-4422(13)70061-9 Read the full article here.
Fratta P. Antisense makes sense for amyotrophic lateral sclerosis C9orf72 Lancet Neurology 2013 DOI: 10.1016/s1474-4422(13)70059-0
New exciting findings announced today provide the first insight into the structure and function of a repeated six letter genetic sequence in an MND gene called C9ORF72.
Understanding the function of C9ORF72, and how it could go wrong to cause MND, could assist researchers in the future to identify potential treatments that target the disease.
The finding was identified by University College London researchers including Dr Adrian Isaacs and Dr Pietro Fratta. Dr Fratta is a recipient of a Medical Research Council/MND Associaiton’s Lady Edith Wolfson Clinical Research Fellowship.
Their findings were published in the reputable scientific journal Scientific Reports on 21 December 2012.
C9ORF72 – the plot thickens
In 2011, MND Association funded researchers discovered that a repeated six-letter code within a gene called C9ORF72 can cause MND and a related condition called fronto-temporal dementia (FTD) for approximately 40% of cases with a family history of MND and/or FTD. Having a family history of MND is rare and affects 5-10% of people with MND.
In people without MND, this six-letter code (GGGGCC) is repeated up to 30 times. In C9ORF72 MND or FTD, this sequence can be excessively repeated between 700 and 1,400 times.
Since this pivotal discovery, researchers have started their journey to search for answers to find out more about C9ORF72 and how it can cause MND.
This study aimed to identify whether the six-letter code normally forms a specific structure when in its copy (RNA) form. Forming a structure normally means that something has a particular role. If this seemingly innocent piece of repetitive code does form a structure, then it could mean that excessively repeating it could cause problems by being over active, or by stopping other functions.
Dr Isaacs who led the study explains,“Nothing is currently known about how the mistake in C9ORF72 kills motor neurones. The mistake in C9ORF72 is similar to mistakes that cause some other neurological diseases.”
“In these diseases the mistake leads to the formation of toxic aggregates of RNA –RNA is a copy of DNA that is made when a gene is switched on and is important for the generation of proteins.”
Dr Issacs and colleagues used advanced analytical chemistry to identify the structure that the repeated six-letter code (GGGGCC) forms and to suggest its potential role.
RNA G-Quadruplex, glorified Battenberg cake
This shape, and structure that has been identified for the repeated six letter code in the copy of C9ORF72 is called an ‘RNA G-quadruplex’.
In real life terms, an RNA G-quadruplex would look –with some artistic license granted – like a Battenberg cake.
The four coloured sponge squares would be the individual letters of the code – all being the ‘GGGG’ part of the sequence running along the length of the structure and forming four ‘slices’.
Each line of four Gs (coloured length of sponge), is stuck together to another line of four Gs in the structure by strong hydrogen bonds (the jam!). This forms the four-square pattern that makes up each ‘slice’. Each line of four Gs is also attached to its phosphate backbone, which is the outermost section of the structure (the marzipan).
The only addition to the Battenberg that’s missing to create an RNA G-quadruplex would be a metal ball, or ion sitting in the middle of each of the four slices.
What does it do?
Having a structure means that the repeated six-letter code is of importance to find out whether it has a function. Having a function would then mean that the genetic expansion could have a detrimental effect on its usual role in the cell.
The forming of these Battenberg cake-like structures means that it could perform a specific role in the body. To date, quadruplexes have been identified as having a number of roles in the body, including editing copies of genes to create functional proteins.
Dr Pietro Fratta explains how this structure could play a role in C9ORF72 MND, “One possibility is that the RNA G-quadruplexes accumulate in motor neurones and then different proteins within the cell somehow bind to this structure and get stuck. As a result the motor neurones malfunction and perhaps even ultimately die.”
Commenting on these findings, MND Association’s Director of Research Development Dr Brian Dickie said “The UCL scientists have opened up an exciting new avenue of research.”
“At the moment we know very little about whether, or how, these RNA structures may be linked to MND, but evidence from other diseases indicates that they are biologically active and therefore likely to be important to the function and health of nerve cells.”
Following this finding, the next steps for researchers will be to determine the function of the G-quadruplex in nerve cells, and the effects of the excessive repeat in MND has on the function of these quadruplexes.
Paper reference: Fratta P. et al. C9orf72 hexanucleotide repeat associated with amyotrophic lateral sclerosis and frontotemporal dementia forms RNA G-quadruplexes. Scientific Reports 2012 DOI: 10.1038/srep01016