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Sarveswaran N, Pamela Y, Reddy AAN, Mustari AP, Parthasarathi A, Mancini AJ, Bishnoi A, Inamadar AC, Olabi B, Browne F, Deshmukh GN, McWilliam K, Vinay K, Srinivas S, Ibbs S, Natarajan S, Rao VR, Zawar V, Gowda VK, Shaikh SS, Moss C, Woods CG, Drissi I. Midfacial Toddler Excoriation syndrome (MiTES): case series, diagnostic criteria and evidence for a pathogenic mechanism. Br J Dermatol 2024:ljae151. [PMID: 38591490 DOI: 10.1093/bjd/ljae151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 04/02/2024] [Accepted: 04/08/2024] [Indexed: 04/10/2024]
Abstract
BACKGROUND PRDM12 polyalanine tract expansions cause two different disorders; Midfacial Toddler Excoriation Syndrome (MiTES) - itch with normal pain sensation associated with homozygous 18 alanines (18A), and congenital insensitivity to pain (CIP) with normal itch with homozygous 19A. Knowledge of the phenotype, genotype, and disease mechanism of MiTES is incomplete. Why PRDM12 18A versus 19A can cause almost opposite phenotypes is unknown; no other poly-alanine or poly-glutamine tract expansion disease causes two such disparate phenotypes. METHODS We assessed the genotype and phenotype of 9 new, 9 atypical, and 6 previously reported patients diagnosed with MiTES. Using cell lines with homozygous PRDM12 of 12A (normal), 18A (MiTES) and 19A (CIP) we examined PRDM12 aggregation and subcellular localisation by image separation confocal microscopy and sub-cellular fractionation western blotting. RESULTS MiTES presents in the first year of life, and in all cases the condition regresses over the first decade leaving scarring. The MiTES phenotype is highly distinctive. Features overlapping with PRDM12-CIP are rarely found. The genotype-phenotype study of PRDM12 polyalanine tract shows that 7A -15A are normal; 16A -18A are associated with MiTES; 19A leads to CIP; and no clinically atypical MiTES cases had an expansion. PRDM12 aggregation and sub-cellular localisation differ significantly between 18A and normal 12A cell lines and between 18A and 19A cell lines. MiTES is a new protein aggregation disease. CONCLUSION We provide diagnostic criteria for MiTES, and improved longitudinal data. MiTES and CIP are distinct phenotypes despite their genotypes varying by a single alanine in the PRDM12 polyalanine tract. We found clear distinctions between the cellular phenotypes of normal, MiTES and CIP cells.. We hypothesise that the developmental environment of the trigeminal ganglion is unique and critically sensitive to prenatal and postnatal levels of PRDM12.
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Affiliation(s)
- Nivedita Sarveswaran
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge Biomedical Campus, Hills Road, Cambridge, UK
| | - Yunisa Pamela
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge Biomedical Campus, Hills Road, Cambridge, UK
- Department of Biomedical Sciences, Faculty of Medicine, Universitas Padjadjaran, Bandung, Indonesia
| | - Akhila A N Reddy
- Dr. Anchala Skin Institute and Research Center, Hyderabad, India
| | - Akash P Mustari
- Department of Dermatology, Venereology and Leprology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | | | - Anthony J Mancini
- Division of Dermatology, Department of Pediatrics, Ann & Robert H. Lurie Children's Hospital of Chicago, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Anuradha Bishnoi
- Department of Dermatology, Venereology and Leprology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Arun C Inamadar
- Department of Dermatology, Shri BM Patil Medical College & Hospital, BLDE University, Bijapur, India
| | - Bayanne Olabi
- Department of Dermatology, Edinburgh Royal Infirmary, UK
| | - Fiona Browne
- Department of Paediatric Dermatology, Children's Health Ireland (CHI) at Crumlin Crumlin, Ireland
| | | | - Kenneth McWilliam
- Paediatric Neurology, Neurosciences Department, Royal hospital for Children and Young people, 50 Little France Cres, Edinburgh, UK
| | - Keshavamurthy Vinay
- Department of Dermatology, Venereology and Leprology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Sahana Srinivas
- Department of Pediatric Dermatology, Indira Gandhi Institute of Child Health, Bangalore, India
| | - Samantha Ibbs
- Department of Paediatric Dermatology, Birmingham Children's Women's and Children's NHS Foundation Trust, Birmingham, UK
| | | | | | - Vijay Zawar
- Department of Dermatology, Dr. Vasantrao Pawar Medical College and Research Center, Nashik, India
| | - Vykuntaraju K Gowda
- Department of Pediatric Neurology, Indira Gandhi Institute of Child Health, Bangalore, Karnataka, India
| | - Samiha S Shaikh
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge Biomedical Campus, Hills Road, Cambridge, UK
| | - Celia Moss
- Department of Paediatric Dermatology, Birmingham Children's Women's and Children's NHS Foundation Trust, Birmingham, UK
- College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham, UK
| | - Christopher G Woods
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge Biomedical Campus, Hills Road, Cambridge, UK
| | - Ichrak Drissi
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge Biomedical Campus, Hills Road, Cambridge, UK
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Tyagi S, Sarveswaran N, Higerd-Rusli GP, Liu S, Dib-Hajj FB, Waxman SG, Dib-Hajj SD. Conserved but not critical: Trafficking and function of NaV1.7 are independent of highly conserved polybasic motifs. Front Mol Neurosci 2023; 16:1161028. [PMID: 37008789 PMCID: PMC10060856 DOI: 10.3389/fnmol.2023.1161028] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Accepted: 03/02/2023] [Indexed: 03/18/2023] Open
Abstract
Non-addictive treatment of chronic pain represents a major unmet clinical need. Peripheral voltage-gated sodium (NaV) channels are an attractive target for pain therapy because they initiate and propagate action potentials in primary afferents that detect and transduce noxious stimuli. NaV1.7 sets the gain on peripheral pain-signaling neurons and is the best validated peripheral ion channel involved in human pain, and previous work has shown that it is transported in vesicles in sensory axons which also carry Rab6a, a small GTPase known to be involved in vesicular packaging and axonal transport. Understanding the mechanism of the association between Rab6a and NaV1.7 could inform therapeutic modalities to decrease trafficking of NaV1.7 to the distal axonal membrane. Polybasic motifs (PBM) have been shown to regulate Rab-protein interactions in a variety of contexts. In this study, we explored whether two PBMs in the cytoplasmic loop that joins domains I and II of human NaV1.7 were responsible for association with Rab6a and regulate axonal trafficking of the channel. Using site-directed mutagenesis we generated NaV1.7 constructs with alanine substitutions in the two PBMs. Voltage-clamp recordings showed that the constructs retain wild-type like gating properties. Optical Pulse-chase Axonal Long-distance (OPAL) imaging in live sensory axons shows that mutations of these PBMs do not affect co-trafficking of Rab6a and NaV1.7, or the accumulation of the channel at the distal axonal surface. Thus, these polybasic motifs are not required for interaction of NaV1.7 with the Rab6a GTPase, or for trafficking of the channel to the plasma membrane.
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Affiliation(s)
- Sidharth Tyagi
- Medical Scientist Training Program, Yale School of Medicine, New Haven, CT, United States
- Center for Neuroscience and Regeneration Research, West Haven, CT, United States
- Department of Neurology, Yale School of Medicine, New Haven, CT, United States
- Center for Restoration of Nervous System Function, VA Connecticut Healthcare System, West Haven, CT, United States
| | - Nivedita Sarveswaran
- Center for Neuroscience and Regeneration Research, West Haven, CT, United States
- Department of Neurology, Yale School of Medicine, New Haven, CT, United States
- Center for Restoration of Nervous System Function, VA Connecticut Healthcare System, West Haven, CT, United States
| | - Grant P. Higerd-Rusli
- Medical Scientist Training Program, Yale School of Medicine, New Haven, CT, United States
- Center for Neuroscience and Regeneration Research, West Haven, CT, United States
- Department of Neurology, Yale School of Medicine, New Haven, CT, United States
- Center for Restoration of Nervous System Function, VA Connecticut Healthcare System, West Haven, CT, United States
| | - Shujun Liu
- Center for Neuroscience and Regeneration Research, West Haven, CT, United States
- Department of Neurology, Yale School of Medicine, New Haven, CT, United States
- Center for Restoration of Nervous System Function, VA Connecticut Healthcare System, West Haven, CT, United States
| | - Fadia B. Dib-Hajj
- Center for Neuroscience and Regeneration Research, West Haven, CT, United States
- Department of Neurology, Yale School of Medicine, New Haven, CT, United States
- Center for Restoration of Nervous System Function, VA Connecticut Healthcare System, West Haven, CT, United States
| | - Stephen G. Waxman
- Center for Neuroscience and Regeneration Research, West Haven, CT, United States
- Department of Neurology, Yale School of Medicine, New Haven, CT, United States
- Center for Restoration of Nervous System Function, VA Connecticut Healthcare System, West Haven, CT, United States
- *Correspondence: Stephen G. Waxman,
| | - Sulayman D. Dib-Hajj
- Center for Neuroscience and Regeneration Research, West Haven, CT, United States
- Department of Neurology, Yale School of Medicine, New Haven, CT, United States
- Center for Restoration of Nervous System Function, VA Connecticut Healthcare System, West Haven, CT, United States
- Sulayman D. Dib-Hajj,
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Higerd-Rusli GP, Alsaloum M, Tyagi S, Sarveswaran N, Estacion M, Akin EJ, Dib-Hajj FB, Liu S, Sosniak D, Zhao P, Dib-Hajj SD, Waxman SG. Depolarizing Na V and Hyperpolarizing K V Channels Are Co-Trafficked in Sensory Neurons. J Neurosci 2022; 42:4794-4811. [PMID: 35589395 PMCID: PMC9188389 DOI: 10.1523/jneurosci.0058-22.2022] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2022] [Revised: 05/04/2022] [Accepted: 05/05/2022] [Indexed: 11/21/2022] Open
Abstract
Neuronal excitability relies on coordinated action of functionally distinction channels. Voltage-gated sodium (NaV) and potassium (KV) channels have distinct but complementary roles in firing action potentials: NaV channels provide depolarizing current while KV channels provide hyperpolarizing current. Mutations and dysfunction of multiple NaV and KV channels underlie disorders of excitability, including pain and epilepsy. Modulating ion channel trafficking may offer a potential therapeutic strategy for these diseases. A fundamental question, however, is whether these channels with distinct functional roles are transported independently or packaged together in the same vesicles in sensory axons. We have used Optical Pulse-Chase Axonal Long-distance imaging to investigate trafficking of NaV and KV channels and other axonal proteins from distinct functional classes in live rodent sensory neurons (from male and female rats). We show that, similar to NaV1.7 channels, NaV1.8 and KV7.2 channels are transported in Rab6a-positive vesicles, and that each of the NaV channel isoforms expressed in healthy, mature sensory neurons (NaV1.6, NaV1.7, NaV1.8, and NaV1.9) is cotransported in the same vesicles. Further, we show that multiple axonal membrane proteins with different physiological functions (NaV1.7, KV7.2, and TNFR1) are cotransported in the same vesicles. However, vesicular packaging of axonal membrane proteins is not indiscriminate, since another axonal membrane protein (NCX2) is transported in separate vesicles. These results shed new light on the development and organization of sensory neuron membranes, revealing complex sorting of axonal proteins with diverse physiological functions into specific transport vesicles.SIGNIFICANCE STATEMENT Normal neuronal excitability is dependent on precise regulation of membrane proteins, including NaV and KV channels, and imbalance in the level of these channels at the plasma membrane could lead to excitability disorders. Ion channel trafficking could potentially be targeted therapeutically, which would require better understanding of the mechanisms underlying trafficking of functionally diverse channels. Optical Pulse-chase Axonal Long-distance imaging in live neurons permitted examination of the specificity of ion channel trafficking, revealing co-packaging of axonal proteins with opposing physiological functions into the same transport vesicles. This suggests that additional trafficking mechanisms are necessary to regulate levels of surface channels, and reveals an important consideration for therapeutic strategies that target ion channel trafficking for the treatment of excitability disorders.
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Affiliation(s)
- Grant P Higerd-Rusli
- MD/PhD Program
- Center for Neuroscience and Regeneration Research and
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut 06510
- Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516
| | - Matthew Alsaloum
- MD/PhD Program
- Center for Neuroscience and Regeneration Research and
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut 06510
- Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516
| | - Sidharth Tyagi
- MD/PhD Program
- Center for Neuroscience and Regeneration Research and
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut 06510
- Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516
| | - Nivedita Sarveswaran
- Center for Neuroscience and Regeneration Research and
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut 06510
- Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516
| | - Mark Estacion
- Center for Neuroscience and Regeneration Research and
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut 06510
- Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516
| | - Elizabeth J Akin
- Center for Neuroscience and Regeneration Research and
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut 06510
- Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516
| | - Fadia B Dib-Hajj
- Center for Neuroscience and Regeneration Research and
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut 06510
- Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516
| | - Shujun Liu
- Center for Neuroscience and Regeneration Research and
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut 06510
- Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516
| | - Daniel Sosniak
- Center for Neuroscience and Regeneration Research and
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut 06510
- Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516
| | - Peng Zhao
- Center for Neuroscience and Regeneration Research and
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut 06510
- Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516
| | - Sulayman D Dib-Hajj
- Center for Neuroscience and Regeneration Research and
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut 06510
- Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516
| | - Stephen G Waxman
- Center for Neuroscience and Regeneration Research and
- Department of Neurology, Yale University School of Medicine, New Haven, Connecticut 06510
- Rehabilitation Research Center, Veterans Affairs Connecticut Healthcare System, West Haven, Connecticut 06516
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Inamadar AC, Vinay K, Olabi B, Sarveswaran N, Bishnoi A, Woods CG, Moss C. Extending the phenotype of midface toddler excoriation syndrome (MiTES): Five new cases in three families with PR domain containing protein 12 (PRDM12) mutations. J Am Acad Dermatol 2019; 81:1415-1417. [PMID: 31128170 DOI: 10.1016/j.jaad.2019.05.036] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2019] [Revised: 05/13/2019] [Accepted: 05/16/2019] [Indexed: 11/29/2022]
Affiliation(s)
- Arun C Inamadar
- Department of Dermatology, Shri BM Patil Medical College & Hospital, BLDE (Deemed to be University), Bijapur, India
| | - Keshavmurthy Vinay
- Department of Dermatology, Post Graduate Institute of Medical Education & Research, Chandigarh, India
| | - Bayanne Olabi
- Department of Dermatology, Edinburgh Royal Infirmary, United Kingdom
| | | | - Anuradha Bishnoi
- Department of Dermatology, Post Graduate Institute of Medical Education & Research, Chandigarh, India
| | - Christopher G Woods
- Cambridge Institute for Medical Research, United Kingdom; Department of Medical Genetics, University of Cambridge, United Kingdom
| | - Celia Moss
- Department of Dermatology, Birmingham Children's Hospital, United Kingdom; College of Medical and Dental Sciences, University of Birmingham, United Kingdom.
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Moss C, Srinivas S, Sarveswaran N, Nahorski M, Gowda V, Browne F, Woods G. Biallelic PRDM12 mutations in MiTES. Br J Dermatol 2018. [DOI: 10.1111/bjd.17217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Moss C, Srinivas SM, Sarveswaran N, Nahorski M, Gowda VK, Browne FM, Woods G. Midface toddler excoriation syndrome (MiTES) can be caused by autosomal recessive biallelic mutations in a gene for congenital insensitivity to pain, PRDM12. Br J Dermatol 2018; 179:1135-1140. [PMID: 29949203 DOI: 10.1111/bjd.16893] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/11/2018] [Indexed: 02/03/2023]
Abstract
BACKGROUND Midface toddler excoriation syndrome (MiTES) is a condition recently reported in three unrelated children. Habitual scratching from the first year of life inflicted deep, chronic, scarring wounds around the nose and eyes. One child had a mild neurological deficit but there was no other evidence of insensitivity to pain. Bilateral distribution and localization to the midface distinguish MiTES from other causes of self-inflicted skin damage such as trigeminal trophic syndrome. An earlier study of five siblings from a consanguineous Irish family, with lesions corresponding to MiTES plus other sensory deficits, showed homozygous mutations in a gene for hereditary sensory and autonomic neuropathy type VIII (HSAN8), PRDM12. OBJECTIVES To study further cases of MiTES, including analysis of PRDM12. METHODS We describe five further children, from four families, with facial lesions typical of MiTES, in whom mutation analysis of PRDM12 was carried out. RESULTS Homozygous or compound heterozygous pathogenic expansions of the PRDM12 polyalanine tract were found in four of five affected individuals, in three families. CONCLUSIONS Our finding of autosomal recessive mutations in PRDM12 in four of five patients with MiTES extends the phenotypic spectrum of PRDM12 mutations, which usually cause HSAN8, characterized by mutilating self-inflicted wounds of the extremities, lips and tongue. By contrast, MiTES shows severe midfacial lesions with little if any evidence of generalized pain insensitivity. The condition is probably genetically heterogeneous, and other congenital insensitivity to pain and HSAN genes such as SCN11A may be implicated. This new understanding of the nature of MiTES, which can masquerade as factitious disease, will facilitate appropriate management.
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Affiliation(s)
- C Moss
- Birmingham Women's and Children's Hospital, Birmingham, U.K
- University of Birmingham, Birmingham, U.K
| | - S M Srinivas
- Department of Pediatric Dermatology, Indira Gandhi Institute of Child Health, Bangalore, Karnataka, India
| | - N Sarveswaran
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, U.K
| | - M Nahorski
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, U.K
| | - V K Gowda
- Department of Pediatric Neurology, Indira Gandhi Institute of Child Health, Bangalore, Karnataka, India
| | - F M Browne
- Department of Dermatology, Our Lady's Children's Hospital, Crumlin, Dublin, Ireland
| | - G Woods
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, U.K
- Department of Medical Genetics, University of Cambridge, Cambridge, U.K
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Moss C, Srinivas SM, Sarveswaran N, Nahorski M, Gowda VK, Browne FM, Woods G. MiTES 中等位基因 PRDM12 突变. Br J Dermatol 2018. [DOI: 10.1111/bjd.17231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Stouffer K, Nahorski M, Moreno P, Sarveswaran N, Menon D, Lee M, Geoffrey Woods C. Functional SNP allele discovery (fSNPd): an approach to find highly penetrant, environmental-triggered genotypes underlying complex human phenotypes. BMC Genomics 2017; 18:944. [PMID: 29202707 PMCID: PMC5716007 DOI: 10.1186/s12864-017-4325-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 11/21/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Significant human diseases/phenotypes exist which require both an environmental trigger event and a genetic predisposition before the disease/phenotype emerges, e.g. Carbamazepine with the rare SNP allele of rs3909184 causing Stevens Johnson syndrome, and aminoglycosides with rs267606617 causing sensory neural deafness. The underlying genotypes are fully penetrant only when the correct environmental trigger(s) occur, otherwise they are silent and harmless. Such diseases/phenotypes will not appear to have a Mendelian inheritance pattern, unless the environmental trigger is very common (>50% per lifetime). The known causative genotypes are likely to be protein-altering SNPs with dominant/semi-dominant effect. We questioned whether other diseases and phenotypes could have a similar aetiology. METHODS We wrote the fSNPd program to analyse multiple exomes from a test cohort simultaneously with the purpose of identifying SNP alleles at a significantly different frequency to that of the general population. fSNPd was tested on trial cohorts, iteratively improved, and modelled for performance against an idealised association study under mutliple parameters. We also assessed the seqeuncing depath of all human exons to determine which were sufficiently well sequenced in an exome to be sued by fSNPd - by assessing forty exomes base by base. RESULTS We describe a simple methodology for the detection of SNPs capable of causing a phenotype triggered by an environmental event. This uses cohorts of relatively small size (30-100 individuals) with the phenotype being investigated, their exomes, and thence seeks SNP allele frequencies significantly different from expected to identify potentially clinically important, protein altering SNP alleles. The strengths and weaknesses of this approach for discovering significant genetic causes of human disease are comparable to Mendelian disease mutation detection and Association Studies. CONCLUSIONS The fSNPd methodology is another approach, and has potentially significant advantage over Association studies in needing far fewer individuals, to detect genes involved in the pathogenesis of a diseases/phenotypes. Furthermore, the SNP alleles identified alter amino acids, potentially making it easier to devise functional assays of protein function to determine pathogenicity.
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Affiliation(s)
- Kaitlin Stouffer
- Cambridge Institute for Medical Research, Wellcome Trust and MRC Building, Addenbrooke's Hospital campus, Cambridge, UK
| | - Michael Nahorski
- Cambridge Institute for Medical Research, Wellcome Trust and MRC Building, Addenbrooke's Hospital campus, Cambridge, UK
| | - Pablo Moreno
- Cambridge Institute for Medical Research, Wellcome Trust and MRC Building, Addenbrooke's Hospital campus, Cambridge, UK
| | - Nivedita Sarveswaran
- Cambridge Institute for Medical Research, Wellcome Trust and MRC Building, Addenbrooke's Hospital campus, Cambridge, UK
| | - David Menon
- Department of Academic Anesthesiology, Addenbrooke's Hospital Campus, Cambridge, UK
| | - Michael Lee
- Department of Academic Anesthesiology, Addenbrooke's Hospital Campus, Cambridge, UK
| | - C Geoffrey Woods
- Cambridge Institute for Medical Research, Wellcome Trust and MRC Building, Addenbrooke's Hospital campus, Cambridge, UK.
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