Models, modifiers and novel treatments of Joubert syndrome
Lead Research Organisation:
Newcastle University
Department Name: Institute of Genetic Medicine
Abstract
Cystic kidney disease accounts for 10% of the 40,000 UK patients requiring renal replacement therapy (dialysis and transplantation). Cystic kidney disease is part of a group of disorders referred to as the "ciliopathies" that cause various combinations of cystic kidney disease, retinal degeneration and brain abnormalities in patients. There are no current disease modifying treatments for these conditions.
The term "ciliopathy" covers a broad spectrum of disorders and patients typically can show a wide range of symptoms. For example, a mutation within the same gene can cause different symptoms in different individual patients. Clearly this complicates efforts to understand the cause of the disease, make accurate diagnoses, and develop specific treatments.
The archetypal ciliopathy is known as Joubert Syndrome (JS) which is predominantly caused by mutations in the CEP290 gene. We have created a mouse model of JS that more closely resembles the human condition than any other and have identified a previously unrecognized abnormality in the kidney that responds positively to drug treatment when we test kidney cells that have been isolated from diseased kidneys.
Our proposal focuses on identifying the factors involved in the complex presentation of ciliopathies to answer the question of why patients carrying mutations in the same gene show different symptoms and if they require different treatments?
To do this, we will breed our JS mutant mice with a different strain of mouse to mimic the genetic complexity of humans (note laboratory mice are inbred, whilst humans are outbred) to give mice with a range of disease severity. In this relatively simple system, it will be possible to identify the factors that affect disease severity.
In addition to the specific benefits to the field of ciliopathies, this proposal will provide a demonstration of the potential of using mouse genetics to understand complex human diseases in general.
This project is likely to provide long-term benefit to patients with inherited ciliopathies as it brings forward in a tangible way the prospect of personalized medicine and individualized treatments for patients. Specifically, the findings of this research proposal will help to categorize and precisely diagnose specific forms of cliliopathy. In parallel, we will assess novel potential treatments tailored to these specific forms. The fact that we have already identified one drug that can restore normal function to JS kidney cells suggests that this next round of research will make a significant step towards a treatment to reduce the morbidity and mortality associated with ciliopathies and reduce the need for dialysis and transplantation in affected patients.
The term "ciliopathy" covers a broad spectrum of disorders and patients typically can show a wide range of symptoms. For example, a mutation within the same gene can cause different symptoms in different individual patients. Clearly this complicates efforts to understand the cause of the disease, make accurate diagnoses, and develop specific treatments.
The archetypal ciliopathy is known as Joubert Syndrome (JS) which is predominantly caused by mutations in the CEP290 gene. We have created a mouse model of JS that more closely resembles the human condition than any other and have identified a previously unrecognized abnormality in the kidney that responds positively to drug treatment when we test kidney cells that have been isolated from diseased kidneys.
Our proposal focuses on identifying the factors involved in the complex presentation of ciliopathies to answer the question of why patients carrying mutations in the same gene show different symptoms and if they require different treatments?
To do this, we will breed our JS mutant mice with a different strain of mouse to mimic the genetic complexity of humans (note laboratory mice are inbred, whilst humans are outbred) to give mice with a range of disease severity. In this relatively simple system, it will be possible to identify the factors that affect disease severity.
In addition to the specific benefits to the field of ciliopathies, this proposal will provide a demonstration of the potential of using mouse genetics to understand complex human diseases in general.
This project is likely to provide long-term benefit to patients with inherited ciliopathies as it brings forward in a tangible way the prospect of personalized medicine and individualized treatments for patients. Specifically, the findings of this research proposal will help to categorize and precisely diagnose specific forms of cliliopathy. In parallel, we will assess novel potential treatments tailored to these specific forms. The fact that we have already identified one drug that can restore normal function to JS kidney cells suggests that this next round of research will make a significant step towards a treatment to reduce the morbidity and mortality associated with ciliopathies and reduce the need for dialysis and transplantation in affected patients.
Technical Summary
We have created a Cep290 mutant mouse model of Joubert Syndrome (JS) that accurately recapitulates human JS, including the variability of phenotype dependent upon genetic background. Furthermore, we have demonstrated that Hh signalling is disrupted in developing renal collecting duct (CDC) cells in these mice and that treatment with a Hh agonist (purmorphamine) can restore normal collecting duct cell function in mutant primary cells ex vivo.
The aim of this proposal is to understand the complexity of JS with a view to identifying potential novel therapeutic targets and compounds. This will be achieved by:
The identification of genetic modifiers of the murine phenotype. C57BL/6 (severe) mice will be crossed with 129/Ola (mild) mutant mice to generate F2 mice that will be screened (Sequenom) to broadly identify loci associated with severity of cystic kidney disease. Affymetrix gene expression arrays will be used to compare kidneys from the parent strains and from a panel of F2 mutant mice to highlight potential modifier genes within these loci.
The identification of novel disease alleles mutated in JS patients. Synentic regions in JS patients having undergone whole exome sequending will be compared with the corresponding to the candidate loci identified in mice. This approach will also serve to validate candidate genes found in mice.
Functional assessment (loss/gain of function) of modifier genes in primary CDCs from JS mice and patients. The effects of loss-of-function (siRNA knockdown) and/or gain of function (lentiviral overexpression) will be evaluated in primary cells from our mouse model and ultimately in JS patient CDCs. The effects of these modifier genes will be assessed in terms of Hh agonist rescue.
This project will address the issue of phenotypic heterogeneity in JS and determine the effects of this heterogeneity upon drug efficacy.
The aim of this proposal is to understand the complexity of JS with a view to identifying potential novel therapeutic targets and compounds. This will be achieved by:
The identification of genetic modifiers of the murine phenotype. C57BL/6 (severe) mice will be crossed with 129/Ola (mild) mutant mice to generate F2 mice that will be screened (Sequenom) to broadly identify loci associated with severity of cystic kidney disease. Affymetrix gene expression arrays will be used to compare kidneys from the parent strains and from a panel of F2 mutant mice to highlight potential modifier genes within these loci.
The identification of novel disease alleles mutated in JS patients. Synentic regions in JS patients having undergone whole exome sequending will be compared with the corresponding to the candidate loci identified in mice. This approach will also serve to validate candidate genes found in mice.
Functional assessment (loss/gain of function) of modifier genes in primary CDCs from JS mice and patients. The effects of loss-of-function (siRNA knockdown) and/or gain of function (lentiviral overexpression) will be evaluated in primary cells from our mouse model and ultimately in JS patient CDCs. The effects of these modifier genes will be assessed in terms of Hh agonist rescue.
This project will address the issue of phenotypic heterogeneity in JS and determine the effects of this heterogeneity upon drug efficacy.
Planned Impact
This project will have impact in the following areas:
Health and well -being of ciliopathy patients: An improvement of day to day health and increase quality of life of patients with ciliopathies is a future benefit of this study. We anticipate this project will hasten the identification of novel treatments to for ciliopathies and cystic kidney disease. We expect our work to become translational within 5 years of this study. The impact of avoiding/postponing renal replacement therapy from an early age are self evident, in terms of health improvement and the complications from dialysis and transplantation.
General reduction in healthcare consumption: Renal replacement therapy costs the NHS 30K per patient per year. Cystic kidney disease accounts for 10% of the 40,000 UK residents on renal replacement therapy. Novel therapies that delay the progression of this disease are likely to reduce healthcare consumption overall.
Researchers within the field of ciliopathies: Identification of novel molecular pathways and disease (modifying) genes in Joubert syndrome will allow insights into related ciliopathies. Following the end of the grant cycle and after publication in peer reviewed discovery journals we would make microarray data and resources (including murine tissue samples) available to the scientific community. The research is of important interest to Rare Diseases consortia in the UK as well as the European Renal Association committee for inherited cystic kidney diseases. We anticipate new collaborations to be formed on the strength of our data and the creation of such novel and unique resources. Our studies will inform the approach to many other ciliopathy diseases as we will elucidate the important mechanistic details involved. Staff working with us on this project will develop skills in personalized medicine which will be applicable to many avenues of basic science research and current and future NHS treatments.
Mouse geneticists and human geneticists: This project will exploit the use of mouse models to probe finer aspects of human disease heterogeneity.
MRC and Genome England 100K Genomes Project: This work will link potential treatments to genetic variants affecting severity of disease and generate a reference framework of genes involved in ciliopathies to help annotate the human 100K genomes project.
Health and well -being of ciliopathy patients: An improvement of day to day health and increase quality of life of patients with ciliopathies is a future benefit of this study. We anticipate this project will hasten the identification of novel treatments to for ciliopathies and cystic kidney disease. We expect our work to become translational within 5 years of this study. The impact of avoiding/postponing renal replacement therapy from an early age are self evident, in terms of health improvement and the complications from dialysis and transplantation.
General reduction in healthcare consumption: Renal replacement therapy costs the NHS 30K per patient per year. Cystic kidney disease accounts for 10% of the 40,000 UK residents on renal replacement therapy. Novel therapies that delay the progression of this disease are likely to reduce healthcare consumption overall.
Researchers within the field of ciliopathies: Identification of novel molecular pathways and disease (modifying) genes in Joubert syndrome will allow insights into related ciliopathies. Following the end of the grant cycle and after publication in peer reviewed discovery journals we would make microarray data and resources (including murine tissue samples) available to the scientific community. The research is of important interest to Rare Diseases consortia in the UK as well as the European Renal Association committee for inherited cystic kidney diseases. We anticipate new collaborations to be formed on the strength of our data and the creation of such novel and unique resources. Our studies will inform the approach to many other ciliopathy diseases as we will elucidate the important mechanistic details involved. Staff working with us on this project will develop skills in personalized medicine which will be applicable to many avenues of basic science research and current and future NHS treatments.
Mouse geneticists and human geneticists: This project will exploit the use of mouse models to probe finer aspects of human disease heterogeneity.
MRC and Genome England 100K Genomes Project: This work will link potential treatments to genetic variants affecting severity of disease and generate a reference framework of genes involved in ciliopathies to help annotate the human 100K genomes project.
Publications
Ramsbottom S
(2015)
Murine Cep290 phenotypes are modified by genetic backgrounds and provide an impetus for investigating disease modifier alleles.
in F1000Research
Slaats GG
(2015)
DNA replication stress underlies renal phenotypes in CEP290-associated Joubert syndrome.
in The Journal of clinical investigation
Iqbal Z
(2016)
Case Report: Cervical chondrocalcinosis as a complication of Gitelman syndrome.
in F1000Research
Al-Hamed MH
(2016)
Renal tubular dysgenesis: antenatal ultrasound scanning and molecular investigations in a Saudi Arabian family.
in Clinical kidney journal
Al-Hamed MH
(2016)
Genetic spectrum of Saudi Arabian patients with antenatal cystic kidney disease and ciliopathy phenotypes using a targeted renal gene panel.
in Journal of medical genetics
Ramsbottom S
(2016)
Regulation of Hedgehog Signalling Inside and Outside the Cell
in Journal of Developmental Biology
Mabillard H
(2017)
Large Retroperitoneal Haemorrhage Following Cyst Rupture in a Patient with Autosomal Dominant Polycystic Kidney Disease.
in Case reports in nephrology
Alkanderi S
(2017)
Lessons learned from a multidisciplinary renal genetics clinic.
in QJM : monthly journal of the Association of Physicians
Sayer JA
(2017)
Progress in Understanding the Genetics of Calcium-Containing Nephrolithiasis.
in Journal of the American Society of Nephrology : JASN
Description | Characterisation of a novel Joubert Syndrome model to accelerate personalised medicine |
Amount | £126,956 (GBP) |
Funding ID | ST_001_20171120 |
Organisation | Kidney Research UK |
Sector | Charity/Non Profit |
Country | United Kingdom |
Start | 09/2018 |
End | 03/2022 |
Description | CiC - Preclinical MRI scanning for therapeutic development in cystic kidney disease |
Amount | £55,721 (GBP) |
Funding ID | BH182162 |
Organisation | Medical Research Council (MRC) |
Sector | Public |
Country | United Kingdom |
Start | 09/2018 |
End | 02/2020 |
Description | Kidney Research Fellowship award |
Amount | £186,049 (GBP) |
Organisation | Kidney Research UK |
Sector | Charity/Non Profit |
Country | United Kingdom |
Start | 01/2017 |
End | 01/2020 |
Description | NIHR |
Amount | £95,659 (GBP) |
Funding ID | PDB058 |
Organisation | Barts Health NHS Trust |
Department | NIHR Biomedical Research Unit |
Sector | Academic/University |
Country | United Kingdom |
Start | 03/2018 |
End | 08/2019 |
Description | Northern Counties Kidney Research Fund |
Amount | £58,000 (GBP) |
Organisation | Northern Counties Kidney Research Fund |
Sector | Charity/Non Profit |
Country | United Kingdom |
Start | 03/2018 |
End | 03/2019 |
Description | Northern Counties Kidney Research Fund Project |
Amount | £24,520 (GBP) |
Organisation | Northern Counties Kidney Research Fund |
Sector | Charity/Non Profit |
Country | United Kingdom |
Start | 11/2017 |
End | 10/2018 |
Description | Rare Disease Research Platform: The renal ciliopathies national network (RCNN) |
Amount | £1,267,381 (GBP) |
Funding ID | MR/Y007808/1 |
Organisation | Medical Research Council (MRC) |
Sector | Public |
Country | United Kingdom |
Start | 06/2023 |
End | 07/2028 |
Description | Collaboration with Friedhelm Hildbrandt |
Organisation | Boston Children's Hospital |
Country | United States |
Sector | Hospitals |
PI Contribution | Sharing of Whole Exome Sequencing Data |
Collaborator Contribution | Friedhelm Hildebrandt has shared hole exome data so we can investigate modifier alleles in Joubert syndrome |
Impact | Genome sequencing |
Start Year | 2017 |
Description | Collaboration with molecular basis of disease and therapeutics |
Organisation | University of Leeds |
Country | United Kingdom |
Sector | Academic/University |
PI Contribution | Working with Colin Johnson Leeds with pharmacological screens of cilia length modulators |
Collaborator Contribution | High throughput analysis of compound library screens. Sharing of cell lines (CRISPR generated CEP290 knock downs) |
Impact | Successful bid for MRC DiMEN PhD studentship |
Start Year | 2016 |
Description | Genetics Matters 2024 Newcastle |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | No |
Geographic Reach | Regional |
Primary Audience | Public/other audiences |
Results and Impact | Genetics Matters" is an annual event organised by Newcastle University to mark the International Rare Disease Day. Currently in its 8th edition, the event consists of a combination of lay-language lectures and hands-on research tables. It is a great opportunity to chat to Newcastle University scientists, and find out about the recent developments in genetic research at Newcastle. The event is held in the beautiful Great Hall of the Discovery Museum, and refreshments (tea/coffee/cake) will be provided. We will have 2-3 short researcher and patient talks, with the majority of the afternoon dedicated to the hands-on and face-to-face research tables. We will cover the cutting-edge topics of genomics, epigenetics, single cell research, stem cells and tissue regeneration, personalised medicine, drug repurposing, mitochondrial donation and cancer research, amongst others. |
Year(s) Of Engagement Activity | 2024 |
URL | https://voice-global.org/opportunities/genetics-matters-2024 |
Description | Genetics Matters Event |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | Regional |
Primary Audience | Public/other audiences |
Results and Impact | This is a public and patient participation event held regularly in Newcastle. It is attended by 100-150 members of the general population and offers lectures, breakout rooms and research tables to allow interactive discussions. |
Year(s) Of Engagement Activity | 2019,2020 |
URL | https://www.voice-global.org/public/opportunities/archived/genetics-matters-2020/ |
Description | Genetics Matters Event Newcastle |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | No |
Geographic Reach | Regional |
Primary Audience | Patients, carers and/or patient groups |
Results and Impact | Genetics Matters" is an annual event organised by Newcastle University to mark the International Rare Disease Day. It is an afternoon of FREE hands-on activities from 1pm-5pm on Sunday 26th February at the Discovery Museum. Patients and publica can meet the scientists and patient representatives, chat about your interests and enjoy science at Newcastle. |
Year(s) Of Engagement Activity | 2023 |
URL | https://ney-genomics.org.uk/genetics-matters-free-event-for-rare-disease-day-26th-feb-2023/ |
Description | Genetics Matters Patient Engagement Day |
Form Of Engagement Activity | Participation in an open day or visit at my research institution |
Part Of Official Scheme? | No |
Geographic Reach | Regional |
Primary Audience | Public/other audiences |
Results and Impact | https://blogs.ncl.ac.uk/katarzynapirog/2018/01/15/save-the-date-genetics-matters-24th-february-2018/ This was a patient/public information day held at the Centre for Life Newcsatle conference centre. There were a series of talks, including an expert patient talk and then a round table discussions relating to different themes. I hosted a table where renal genetics was showcased and discussed. 90 people attended the event. "We are pleased to announce we'll be hosting our popular Genetics Matters event again on the 24th of February 2018 as part of the international Rare Disease Day. Come meet the scientists, touch real specimens, chat about rare diseases and hear about the exciting state of the art research at Newcastle University. "Genetics Matters" annual event serves to showcase genetic research and to give the patient and charity organisations a voice and a platform to interact with the members of general public. The theme of the Rare Disease Day in 2018 is "Research", recognising the state-of-the-art research into rare diseases in the UK and the crucial role that patients play in research by voicing their needs and instigating change. This event is free to attend, however, the places are limited. To register, please provide your details below. Come join us for an afternoon of chatting about science, and find out about state of the art research at Newcastle University" |
Year(s) Of Engagement Activity | 2018 |
URL | https://blogs.ncl.ac.uk/katarzynapirog/2018/01/15/save-the-date-genetics-matters-24th-february-2018/ |
Description | PKD patient information day, Freeman Hospital, Newcastle |
Form Of Engagement Activity | Participation in an activity, workshop or similar |
Part Of Official Scheme? | No |
Geographic Reach | National |
Primary Audience | Patients, carers and/or patient groups |
Results and Impact | Raising awareness of cystic kidney disease, especially genetic factors and research methodologies. 90 patients and their carers attended for a full day of interactive talks regarding polycystic kidney disease. |
Year(s) Of Engagement Activity | 2018 |
Description | Parents of patients invited to the lab for a tour and discussion |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | Regional |
Primary Audience | Patients, carers and/or patient groups |
Results and Impact | More awareness of laboratory research |
Year(s) Of Engagement Activity | 2018 |
Description | Patient / family conference |
Form Of Engagement Activity | A talk or presentation |
Part Of Official Scheme? | No |
Geographic Reach | International |
Primary Audience | Patients, carers and/or patient groups |
Results and Impact | Talking to patients and their carers/family members regarding the future possible treatments of JBTS. Many family members wishing to take part in research projects. |
Year(s) Of Engagement Activity | 2015 |