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Zhang L, Armour K, Chen JY, Mylona A, Yang M, Andersen GR, Maciejewki JP, Bakrania P, Lin F. Humanization of a mouse anti-human complement C6 monoclonal antibody as a potential therapeutic for certain complement-mediated diseases. Mol Immunol 2024; 170:19-25. [PMID: 38598870 DOI: 10.1016/j.molimm.2024.03.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Revised: 03/08/2024] [Accepted: 03/26/2024] [Indexed: 04/12/2024]
Abstract
The assembly of tissue-damaging membrane attack complexes (MACs; C5b-9) is a major mechanism by which excessive complement activation causes diseases. We previously developed a mouse anti-human C6 monoclonal antibody (mAb) 1C9 that selectively inhibits the assembly of MACs in human and non-human primates. In this project, we found that 1C9 also cross-reacted with rat and guinea pig C6, and determined its binding domains on C6 using different truncated C6 proteins. We then humanized the anti-C6 mAb by molecular modeling and complementarity-determining region grafting. After screening a library of 276 humanized variants with different combinations of humanized light and heavy chains in biophysical assays, we identified clone 3713 with the best developability profile, and an increased affinity against C6 when compared with the parental 1C9 mAb. This humanized 3713 mAb inhibited human, monkey, and rat complement-mediated hemolysis in vitro, and more importantly, it significantly reduced complement-mediated hemolysis in vivo in rats. These results demonstrated the successful humanization of the anti-C6 mAb and suggested that the humanized 3713 mAb could be further developed as a new therapeutic that selectively targets MAC for certain complement-mediated pathological conditions.
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Affiliation(s)
- Lingjun Zhang
- Department of Immunity and Inflammation, Lerner Research Institute, Cleveland Clinic, OH, USA
| | | | - Jin Y Chen
- Department of Immunity and Inflammation, Lerner Research Institute, Cleveland Clinic, OH, USA
| | | | - Maojing Yang
- Department of Immunity and Inflammation, Lerner Research Institute, Cleveland Clinic, OH, USA
| | - Gregers R Andersen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - Jaroslaw P Maciejewki
- Department of Translational Hematology and Oncology Research, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
| | | | - Feng Lin
- Department of Immunity and Inflammation, Lerner Research Institute, Cleveland Clinic, OH, USA.
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2
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Sawmynaden K, Wong N, Davies S, Cowan R, Brown R, Tang D, Henry M, Tickle D, Matthews D, Carr M, Bakrania P, Hoi Ting H, Hall G. Co-crystallisation and humanisation of an anti-HER2 single-domain antibody as a theranostic tool. PLoS One 2023; 18:e0288259. [PMID: 37459326 PMCID: PMC10351726 DOI: 10.1371/journal.pone.0288259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Accepted: 06/22/2023] [Indexed: 07/20/2023] Open
Abstract
Human epidermal growth factor receptor-2 (HER2) is a well-recognised biomarker associated with 25% of breast cancers. In most cases, early detection and/or treatment correlates with an increased chance of survival. This study, has identified and characterised a highly specific anti-HER2 single-domain antibody (sdAb), NM-02, as a potential theranostic tool. Complete structural description by X-ray crystallography has revealed a non-overlapping epitope with current anti-HER2 antibodies. To reduce the immunogenicity risk, NM-02 underwent a humanisation process and retained wild type-like binding properties. To further de-risk the progression towards chemistry, manufacturing and control (CMC) we performed full developability profiling revealing favourable thermal and physical biochemical 'drug-like' properties. Finally, the application of the lead humanised NM-02 candidate (variant K) for HER2-specific imaging purposes was demonstrated using breast cancer HER2+/BT474 xenograft mice.
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Affiliation(s)
| | | | - Sarah Davies
- LifeArc, Open Innovation Campus, Stevenage, United Kingdom
| | - Richard Cowan
- Department of Molecular and Cell Biology, Leicester Institute of Structural and Chemical Biology, University of Leicester, Leicester, United Kingdom
| | - Richard Brown
- LifeArc, Open Innovation Campus, Stevenage, United Kingdom
| | - David Tang
- LifeArc, Open Innovation Campus, Stevenage, United Kingdom
| | - Maud Henry
- LifeArc, Open Innovation Campus, Stevenage, United Kingdom
| | - David Tickle
- LifeArc, Open Innovation Campus, Stevenage, United Kingdom
| | - David Matthews
- LifeArc, Open Innovation Campus, Stevenage, United Kingdom
| | - Mark Carr
- Department of Molecular and Cell Biology, Leicester Institute of Structural and Chemical Biology, University of Leicester, Leicester, United Kingdom
| | | | | | - Gareth Hall
- Department of Molecular and Cell Biology, Leicester Institute of Structural and Chemical Biology, University of Leicester, Leicester, United Kingdom
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3
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Chapman TM, Gillen KJ, Wallace C, Lee MT, Bakrania P, Khurana P, Coombs PJ, Stennett L, Fox S, Bureau EA, Brownlees J, Melton DW, Saxty B. Catechols and 3-hydroxypyridones as inhibitors of the DNA repair complex ERCC1-XPF. Bioorg Med Chem Lett 2015; 25:4097-103. [PMID: 26318993 DOI: 10.1016/j.bmcl.2015.08.031] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Revised: 08/07/2015] [Accepted: 08/11/2015] [Indexed: 11/29/2022]
Abstract
Catechol-based inhibitors of ERCC1-XPF endonuclease activity were identified from a high-throughput screen. Exploration of the structure-activity relationships within this series yielded compound 13, which displayed an ERCC1-XPF IC50 of 0.6 μM, high selectivity against FEN-1 and DNase I and activity in nucleotide excision repair, cisplatin enhancement and γH2AX assays in A375 melanoma cells. Screening of fragments as potential alternatives to the catechol group revealed that 3-hydroxypyridones are able to inhibit ERCC1-XPF with high ligand efficiency, and elaboration of the hit gave compounds 36 and 37 which showed promising ERCC1-XPF IC50 values of <10 μM.
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Affiliation(s)
- Timothy M Chapman
- Centre for Therapeutics Discovery, MRC Technology, 1-3 Burtonhole Lane, Mill Hill, London NW7 1AD, UK
| | - Kevin J Gillen
- Centre for Therapeutics Discovery, MRC Technology, 1-3 Burtonhole Lane, Mill Hill, London NW7 1AD, UK
| | - Claire Wallace
- Centre for Therapeutics Discovery, MRC Technology, 1-3 Burtonhole Lane, Mill Hill, London NW7 1AD, UK
| | - Maximillian T Lee
- Centre for Therapeutics Discovery, MRC Technology, 1-3 Burtonhole Lane, Mill Hill, London NW7 1AD, UK
| | - Preeti Bakrania
- Centre for Therapeutics Discovery, MRC Technology, 1-3 Burtonhole Lane, Mill Hill, London NW7 1AD, UK
| | - Puneet Khurana
- Centre for Therapeutics Discovery, MRC Technology, 1-3 Burtonhole Lane, Mill Hill, London NW7 1AD, UK
| | - Peter J Coombs
- Centre for Therapeutics Discovery, MRC Technology, 1-3 Burtonhole Lane, Mill Hill, London NW7 1AD, UK
| | - Laura Stennett
- Centre for Therapeutics Discovery, MRC Technology, 1-3 Burtonhole Lane, Mill Hill, London NW7 1AD, UK
| | - Simon Fox
- Centre for Therapeutics Discovery, MRC Technology, 1-3 Burtonhole Lane, Mill Hill, London NW7 1AD, UK
| | - Emilie A Bureau
- Centre for Therapeutics Discovery, MRC Technology, 1-3 Burtonhole Lane, Mill Hill, London NW7 1AD, UK
| | - Janet Brownlees
- Centre for Therapeutics Discovery, MRC Technology, 1-3 Burtonhole Lane, Mill Hill, London NW7 1AD, UK
| | - David W Melton
- MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, MRC Human Genetics Unit, Western General Hospital, Crewe Road, Edinburgh EH4 2XU, UK
| | - Barbara Saxty
- Centre for Therapeutics Discovery, MRC Technology, 1-3 Burtonhole Lane, Mill Hill, London NW7 1AD, UK
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4
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Chapman TM, Wallace C, Gillen KJ, Bakrania P, Khurana P, Coombs PJ, Fox S, Bureau EA, Brownlees J, Melton DW, Saxty B. N-Hydroxyimides and hydroxypyrimidinones as inhibitors of the DNA repair complex ERCC1-XPF. Bioorg Med Chem Lett 2015; 25:4104-8. [PMID: 26321360 DOI: 10.1016/j.bmcl.2015.08.024] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Revised: 08/06/2015] [Accepted: 08/07/2015] [Indexed: 11/19/2022]
Abstract
A high throughput screen allowed the identification of N-hydroxyimide inhibitors of ERCC1-XPF endonuclease activity with micromolar potency, but they showed undesirable selectivity profiles against FEN-1. A scaffold hop to a hydroxypyrimidinone template gave compounds with similar potency but allowed selectivity to be switched in favour of ERCC1-XPF over FEN-1. Further exploration of the structure-activity relationships around this chemotype gave sub-micromolar inhibitors with >10-fold selectivity for ERCC1-XPF over FEN-1.
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Affiliation(s)
- Timothy M Chapman
- Centre for Therapeutics Discovery, MRC Technology, 1-3 Burtonhole Lane, Mill Hill, London NW7 1AD, UK
| | - Claire Wallace
- Centre for Therapeutics Discovery, MRC Technology, 1-3 Burtonhole Lane, Mill Hill, London NW7 1AD, UK
| | - Kevin J Gillen
- Centre for Therapeutics Discovery, MRC Technology, 1-3 Burtonhole Lane, Mill Hill, London NW7 1AD, UK
| | - Preeti Bakrania
- Centre for Therapeutics Discovery, MRC Technology, 1-3 Burtonhole Lane, Mill Hill, London NW7 1AD, UK
| | - Puneet Khurana
- Centre for Therapeutics Discovery, MRC Technology, 1-3 Burtonhole Lane, Mill Hill, London NW7 1AD, UK
| | - Peter J Coombs
- Centre for Therapeutics Discovery, MRC Technology, 1-3 Burtonhole Lane, Mill Hill, London NW7 1AD, UK
| | - Simon Fox
- Centre for Therapeutics Discovery, MRC Technology, 1-3 Burtonhole Lane, Mill Hill, London NW7 1AD, UK
| | - Emilie A Bureau
- Centre for Therapeutics Discovery, MRC Technology, 1-3 Burtonhole Lane, Mill Hill, London NW7 1AD, UK
| | - Janet Brownlees
- Centre for Therapeutics Discovery, MRC Technology, 1-3 Burtonhole Lane, Mill Hill, London NW7 1AD, UK
| | - David W Melton
- MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, MRC Human Genetics Unit, Western General Hospital, Crewe Road, Edinburgh EH4 2XU, UK
| | - Barbara Saxty
- Centre for Therapeutics Discovery, MRC Technology, 1-3 Burtonhole Lane, Mill Hill, London NW7 1AD, UK
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5
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McNeil EM, Astell KR, Ritchie AM, Shave S, Houston DR, Bakrania P, Jones HM, Khurana P, Wallace C, Chapman T, Wear MA, Walkinshaw MD, Saxty B, Melton DW. Inhibition of the ERCC1-XPF structure-specific endonuclease to overcome cancer chemoresistance. DNA Repair (Amst) 2015; 31:19-28. [PMID: 25956741 DOI: 10.1016/j.dnarep.2015.04.002] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Revised: 04/07/2015] [Accepted: 04/10/2015] [Indexed: 01/23/2023]
Abstract
ERCC1-XPF is a structure-specific endonuclease that is required for the repair of DNA lesions, generated by the widely used platinum-containing cancer chemotherapeutics such as cisplatin, through the Nucleotide Excision Repair and Interstrand Crosslink Repair pathways. Based on mouse xenograft experiments, where ERCC1-deficient melanomas were cured by cisplatin therapy, we proposed that inhibition of ERCC1-XPF could enhance the effectiveness of platinum-based chemotherapy. Here we report the identification and properties of inhibitors against two key targets on ERCC1-XPF. By targeting the ERCC1-XPF interaction domain we proposed that inhibition would disrupt the ERCC1-XPF heterodimer resulting in destabilisation of both proteins. Using in silico screening, we identified an inhibitor that bound to ERCC1-XPF in a biophysical assay, reduced the level of ERCC1-XPF complexes in ovarian cancer cells, inhibited Nucleotide Excision Repair and sensitised melanoma cells to cisplatin. We also utilised high throughput and in silico screening to identify the first reported inhibitors of the other key target, the XPF endonuclease domain. We demonstrate that two of these compounds display specificity in vitro for ERCC1-XPF over two other endonucleases, bind to ERCC1-XPF, inhibit Nucleotide Excision Repair in two independent assays and specifically sensitise Nucleotide Excision Repair-proficient, but not Nucleotide Excision Repair-deficient human and mouse cells to cisplatin.
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Affiliation(s)
- Ewan M McNeil
- MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, MRC Human Genetics Unit, Western General Hospital, Crewe Road, Edinburgh EH4 2XU, UK
| | - Katy R Astell
- MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, MRC Human Genetics Unit, Western General Hospital, Crewe Road, Edinburgh EH4 2XU, UK
| | - Ann-Marie Ritchie
- MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, MRC Human Genetics Unit, Western General Hospital, Crewe Road, Edinburgh EH4 2XU, UK
| | - Steven Shave
- Centre for Translational and Chemical Biology, School of Biological Sciences, University of Edinburgh, Michael Swann Building, The King's Buildings, Mayfield Road, Edinburgh EH9 3JR, UK
| | - Douglas R Houston
- Centre for Translational and Chemical Biology, School of Biological Sciences, University of Edinburgh, Michael Swann Building, The King's Buildings, Mayfield Road, Edinburgh EH9 3JR, UK
| | - Preeti Bakrania
- Centre for Therapeutics Discovery, MRC Technology, 1-3 Burtonhole Lane, Mill Hill, London NW7 1AD, UK
| | - Hayley M Jones
- Centre for Therapeutics Discovery, MRC Technology, 1-3 Burtonhole Lane, Mill Hill, London NW7 1AD, UK
| | - Puneet Khurana
- Centre for Therapeutics Discovery, MRC Technology, 1-3 Burtonhole Lane, Mill Hill, London NW7 1AD, UK
| | - Claire Wallace
- Centre for Therapeutics Discovery, MRC Technology, 1-3 Burtonhole Lane, Mill Hill, London NW7 1AD, UK
| | - Tim Chapman
- Centre for Therapeutics Discovery, MRC Technology, 1-3 Burtonhole Lane, Mill Hill, London NW7 1AD, UK
| | - Martin A Wear
- Centre for Translational and Chemical Biology, School of Biological Sciences, University of Edinburgh, Michael Swann Building, The King's Buildings, Mayfield Road, Edinburgh EH9 3JR, UK
| | - Malcolm D Walkinshaw
- Centre for Translational and Chemical Biology, School of Biological Sciences, University of Edinburgh, Michael Swann Building, The King's Buildings, Mayfield Road, Edinburgh EH9 3JR, UK
| | - Barbara Saxty
- Centre for Therapeutics Discovery, MRC Technology, 1-3 Burtonhole Lane, Mill Hill, London NW7 1AD, UK
| | - David W Melton
- MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, MRC Human Genetics Unit, Western General Hospital, Crewe Road, Edinburgh EH4 2XU, UK.
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Bakrania P, Ugur Iseri SA, Wyatt AW, Bunyan DJ, Lam WWK, Salt A, Ramsay J, Robinson DO, Ragge NK. Sonic hedgehog mutations are an uncommon cause of developmental eye anomalies. Am J Med Genet A 2010; 152A:1310-3. [PMID: 20425842 DOI: 10.1002/ajmg.a.33239] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Preeti Bakrania
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
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Wyatt A, Bakrania P, Bunyan DJ, Osborne RJ, Crolla JA, Salt A, Ayuso C, Newbury-Ecob R, Abou-Rayyah Y, Collin JRO, Robinson D, Ragge N. Novel heterozygous OTX2 mutations and whole gene deletions in anophthalmia, microphthalmia and coloboma. Hum Mutat 2008; 29:E278-83. [PMID: 18781617 DOI: 10.1002/humu.20869] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Severe ocular malformations, including anophthalmia-microphthalmia (AM), are responsible for around 25% of severe visual impairment in childhood. Recurrent interstitial deletions of 14q22-23 are associated with AM and a wide range of extra-ocular phenotypes including brain anomalies. The homeobox gene OTX2 is located at 14q22.3 and has recently been identified as mutated in AM patients. Eight human OTX2 mutations have been reported in subjects with severe eye malformations, including AM, and variable developmental delay. We screened a novel AM cohort for mutations and deletions in OTX2, and identified four new mutations in six individuals and two cases of whole gene deletions. Our data suggest that OTX2 mutations and deletions account for 2-3% of AM cases.
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Affiliation(s)
- Alexander Wyatt
- Dept of Physiology, Anatomy and Genetics, University of Oxford, South Parks Road, Oxford, OX1 3QX
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Bakrania P, Efthymiou M, Klein JC, Salt A, Bunyan DJ, Wyatt A, Ponting CP, Martin A, Williams S, Lindley V, Gilmore J, Restori M, Robson AG, Neveu MM, Holder GE, Collin JRO, Robinson DO, Farndon P, Johansen-Berg H, Gerrelli D, Ragge NK. Mutations in BMP4 cause eye, brain, and digit developmental anomalies: overlap between the BMP4 and hedgehog signaling pathways. Am J Hum Genet 2008; 82:304-19. [PMID: 18252212 DOI: 10.1016/j.ajhg.2007.09.023] [Citation(s) in RCA: 191] [Impact Index Per Article: 11.9] [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] [Received: 07/20/2007] [Revised: 09/18/2007] [Accepted: 09/24/2007] [Indexed: 11/28/2022] Open
Abstract
Developmental ocular malformations, including anophthalmia-microphthalmia (AM), are heterogeneous disorders with frequent sporadic or non-Mendelian inheritance. Recurrent interstitial deletions of 14q22-q23 have been associated with AM, sometimes with poly/syndactyly and hypopituitarism. We identify two further cases of AM (one with associated pituitary anomalies) with a 14q22-q23 deletion. Using a positional candidate gene approach, we analyzed the BMP4 (Bone Morphogenetic Protein-4) gene and identified a frameshift mutation (c.226del2, p.S76fs104X) that segregated with AM, retinal dystrophy, myopia, brain anomalies, and polydactyly in a family and a nonconservative missense mutation (c.278A-->G, p.E93G) in a highly conserved base in another family. MR imaging and tractography in the c.226del2 proband revealed a primary brain developmental disorder affecting thalamostriatal and callosal pathways, also present in the affected grandmother. Using in situ hybridization in human embryos, we demonstrate expression of BMP4 in optic vesicle, developing retina and lens, pituitary region, and digits strongly supporting BMP4 as a causative gene for AM, pituitary, and poly/syndactyly. Because BMP4 interacts with HH signaling genes in animals, we evaluated gene expression in human embryos and demonstrate cotemporal and cospatial expression of BMP4 and HH signaling genes. We also identified four cases, some of whom had retinal dystrophy, with "low-penetrant" mutations in both BMP4 and HH signaling genes: SHH (Sonic Hedgehog) or PTCH1 (Patched). We propose that BMP4 is a major gene for AM and/or retinal dystrophy and brain anomalies and may be a candidate gene for myopia and poly/syndactyly. Our finding of low-penetrant variants in BMP4 and HH signaling partners is suggestive of an interaction between the two pathways in humans.
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Affiliation(s)
- Preeti Bakrania
- Department of Physiology, Anatomy and Genetics, University of Oxford, South Parks Road, Oxford OX1 3QX, UK
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Bakrania P, Robinson DO, Bunyan DJ, Salt A, Martin A, Crolla JA, Wyatt A, Fielder A, Ainsworth J, Moore A, Read S, Uddin J, Laws D, Pascuel-Salcedo D, Ayuso C, Allen L, Collin JRO, Ragge NK. SOX2 anophthalmia syndrome: 12 new cases demonstrating broader phenotype and high frequency of large gene deletions. Br J Ophthalmol 2007; 91:1471-6. [PMID: 17522144 PMCID: PMC2095460 DOI: 10.1136/bjo.2007.117929] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
BACKGROUND Developmental eye anomalies, which include anophthalmia (absent eye) or microphthalmia (small eye) are an important cause of severe visual impairment in infants and young children. Heterozygous mutations in SOX2, a SOX1B-HMG box transcription factor, have been found in up to 10% of individuals with severe microphthalmia or anophthalmia and such mutations could also be associated with a range of non-ocular abnormalities. METHODS We performed mutation analysis on a new cohort of 120 patients with congenital eye abnormalities, mainly anophthalmia, microphthalmia and coloboma. Multiplex ligation-dependent probe amplification (MLPA) and fluorescence in situ hybridisation (FISH) were used to detect whole gene deletion. RESULTS We identified four novel intragenic SOX2 mutations (one single base deletion, one single base duplication and two point mutations generating premature translational termination codons) and two further cases with the previously reported c.70del20 mutation. Of 52 patients with severe microphthalmia or anophthalmia analysed by MLPA, 5 were found to be deleted for the whole SOX2 gene and 1 had a partial deletion. In two of these, FISH studies identified sub-microscopic deletions involving a minimum of 328 Kb and 550 Kb. The SOX2 phenotypes include a patient with anophthalmia, oesophageal abnormalities and horseshoe kidney, and a patient with a retinal dystrophy implicating SOX2 in retinal development. CONCLUSION Our results provide further evidence that SOX2 haploinsufficiency is a common cause of severe developmental ocular malformations and that background genetic variation determines the varying phenotypes. Given the high incidence of whole gene deletion we recommend that all patients with severe microphthalmia or anophthalmia, including unilateral cases be screened by MLPA and FISH for SOX2 deletions.
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Affiliation(s)
- P Bakrania
- Dept of Physiology, Anatomy and Genetics, Le Gros Clark Building, South Parks Road, Oxford, OX1 3QX, United Kingdom
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