@article {2020, title = {Expanding the phenotype of TTLL5-associated retinal dystrophy: a case series.}, journal = {Orphanet J Rare Dis}, volume = {17}, year = {2022}, month = {2022 04 01}, pages = {146}, abstract = {

BACKGROUND: Inherited retinal dystrophies describe a heterogeneous group of retinal diseases that lead to the irreversible degeneration of rod and cone photoreceptors and eventual blindness. Recessive loss-of-function mutations in Tubulin Tyrosine Ligase Like 5 (TTLL5) represent a recently described cause of inherited cone-rod and cone dystrophy. This study describes the unusual phenotypes of three patients with autosomal recessive mutations in TTLL5. Examination of these patients included funduscopic evaluation, spectral-domain optical coherence tomography, short-wavelength autofluorescence, and full-field electroretinography (ffERG). Genetic diagnoses were confirmed using whole exome capture. Protein modeling of the identified variants was performed to explore potential genotype-phenotype correlations.

RESULTS: Genetic testing revealed five novel variants in TTLL5 in three unrelated patients with retinal dystrophy. Clinical imaging demonstrated features of sectoral cone-rod dystrophy and cone dystrophy, with phenotypic variability seen across all three patients. One patient also developed high-frequency hearing loss during a similar time period as the onset of retinal disease, potentially suggestive of a syndromic disorder. Retinal structure findings were corroborated with functional measures including ffERG findings that supported these diagnoses. Modeling of the five variants suggest that they cause different effects on protein function, providing a potential reason for genotype-phenotype correlation in these patients.

CONCLUSIONS: The authors report retinal phenotypic findings in three unrelated patients with novel mutations causing autosomal recessive TTLL5-mediated retinal dystrophy. These findings broaden the understanding of the phenotypes associated with TTLL5-mediated retinal disease and suggest that mutations in TTLL5 should be considered as a potential cause of sectoral retinal dystrophy in addition to cone-rod and cone dystrophies.

}, keywords = {Carrier Proteins, Electroretinography, Genetic Association Studies, Humans, Mutation, Phenotype, Retinal Dystrophies}, issn = {1750-1172}, doi = {10.1186/s13023-022-02295-9}, author = {Oh, Jin Kyun and Vargas Del Valle, Jos{\'e} G and Lima de Carvalho, Jose Ronaldo and Sun, Young Joo and Levi, Sarah R and Ryu, Joseph and Yang, Jing and Nagasaki, Takayuki and Emanuelli, Andres and Rasool, Nailyn and Allikmets, Rando and Sparrow, Janet R and Izquierdo, Natalio J and Duncan, Jacque L and Mahajan, Vinit B and Tsang, Stephen H} } @article {699, title = {Structural modeling of a novel CAPN5 mutation that causes uveitis and neovascular retinal detachment.}, journal = {PLoS One}, volume = {10}, year = {2015}, month = {2015}, pages = {e0122352}, abstract = {

CAPN5 mutations have been linked to autosomal dominant neovascular inflammatory vitreoretinopathy (ADNIV), a blinding autoimmune eye disease. Here, we link a new CAPN5 mutation to ADNIV and model the three-dimensional structure of the resulting mutant protein. In our study, a kindred with inflammatory vitreoretinopathy was evaluated by clinical eye examinations, DNA sequencing, and protein structural modeling to investigate the disease-causing mutation. Two daughters of an affected mother demonstrated symptoms of stage III ADNIV, with posterior uveitis, cystoid macular edema, intraocular fibrosis, retinal neovascularization, retinal degeneration, and cataract. The women also harbored a novel guanine to thymine (c.750G\>T, p.Lys250Asn) missense mutation in exon 6 of CAPN5, a gene that encodes a calcium-activated cysteine protease, calpain-5. Modeling based on the structures of all known calpains revealed the mutation falls within a calcium-sensitive flexible gating loop that controls access to the catalytic groove. Three-dimensional modeling placed the new mutation in a region adjacent to two previously identified disease-causing mutations, all three of which likely disrupt hydrogen bonding within the gating loop, yielding a CAPN5 with altered enzymatic activity. This is the third case of a CAPN5 mutation leading to inherited uveitis and neovascular vitreoretinopathy, suggesting patients with ADNIV features should be tested for CAPN5 mutations. Structural modeling of novel variants can be used to support mechanistic consequences of the disease-causing variants.

}, keywords = {Base Sequence, Calpain, Computational Biology, DNA Primers, Female, Fluorescein Angiography, Humans, Models, Molecular, Molecular Sequence Data, Mutation, Missense, Pedigree, Phenotype, Protein Conformation, Retinal Detachment, Sequence Analysis, DNA, Tomography, Optical Coherence, Uveitis, Vitreoretinopathy, Proliferative}, issn = {1932-6203}, doi = {10.1371/journal.pone.0122352}, author = {Bassuk, Alexander G and Yeh, Steven and Wu, Shu and Martin, Daniel F and Tsang, Stephen H and Gakhar, Lokesh and Mahajan, Vinit B} } @article {97, title = {Genome-wide generation and systematic phenotyping of knockout mice reveals new roles for many genes.}, journal = {Cell}, volume = {154}, year = {2013}, month = {2013 Jul 18}, pages = {452-64}, abstract = {

Mutations in whole organisms are powerful ways of interrogating gene function in a realistic context. We describe a program, the Sanger Institute Mouse Genetics Project, that provides a step toward the aim of knocking out all genes and screening each line for a broad range of traits. We found that hitherto unpublished genes were as likely to reveal phenotypes as known genes, suggesting that novel genes represent a rich resource for investigating the molecular basis of disease. We found many unexpected phenotypes detected only because we screened for them, emphasizing the value of screening all mutants for a wide range of traits. Haploinsufficiency and pleiotropy were both surprisingly common. Forty-two percent of genes were essential for viability, and these were less likely to have a paralog and more likely to contribute to a protein complex than other genes. Phenotypic data and more than 900 mutants are openly available for further analysis. PAPERCLIP:

}, keywords = {Animals, Disease, Disease Models, Animal, Female, Genes, Essential, Genetic Techniques, Genome-Wide Association Study, Male, Mice, Mice, Knockout, Phenotype}, author = {White, Jacqueline K and Gerdin, Anna-Karin and Karp, Natasha A and Ryder, Ed and Buljan, Marija and Bussell, James N and Salisbury, Jennifer and Clare, Simon and Ingham, Neil J and Podrini, Christine and Houghton, Richard and Estabel, Jeanne and Bottomley, Joanna R and Melvin, David G and Sunter, David and Adams, Niels C and Tannahill, David and Logan, Darren W and Macarthur, Daniel G and Flint, Jonathan and Mahajan, Vinit B and Tsang, Stephen H and Smyth, Ian and Watt, Fiona M and Skarnes, William C and Dougan, Gordon and Adams, David J and Ramirez-Solis, Ramiro and Bradley, Allan and Steel, Karen P} } @article {115, title = {Calpain-5 mutations cause autoimmune uveitis, retinal neovascularization, and photoreceptor degeneration.}, journal = {PLoS Genet}, volume = {8}, year = {2012}, month = {2012}, pages = {e1003001}, abstract = {

Autosomal dominant neovascular inflammatory vitreoretinopathy (ADNIV) is an autoimmune condition of the eye that sequentially mimics uveitis, retinitis pigmentosa, and proliferative diabetic retinopathy as it progresses to complete blindness. We identified two different missense mutations in the CAPN5 gene in three ADNIV kindreds. CAPN5 encodes calpain-5, a calcium-activated cysteine protease that is expressed in retinal photoreceptor cells. Both mutations cause mislocalization from the cell membrane to the cytosol, and structural modeling reveals that both mutations lie within a calcium-sensitive domain near the active site. CAPN5 is only the second member of the large calpain gene family to cause a human Mendelian disorder, and this is the first report of a specific molecular cause for autoimmune eye disease. Further investigation of these mutations is likely to provide insight into the pathophysiologic mechanisms of common diseases ranging from autoimmune disorders to diabetic retinopathy.

}, keywords = {Amino Acid Sequence, Base Sequence, Calpain, Cell Line, Cells, Cultured, Choroid Diseases, Exome, Exons, Eye Diseases, Hereditary, Female, Gene Expression, Genetic Linkage, Humans, Male, Models, Molecular, Molecular Sequence Data, Mutation, Pedigree, Phenotype, Photoreceptor Cells, Vertebrate, Protein Conformation, Protein Transport, Retinal Degeneration, Sequence Alignment}, author = {Mahajan, Vinit B and Skeie, Jessica M and Bassuk, Alexander G and Fingert, John H and Braun, Terry A and Daggett, Heather T and Folk, James C and Sheffield, Val C and Stone, Edwin M} } @article {781, title = {Automated discovery and quantification of image-based complex phenotypes: a twin study of drusen phenotypes in age-related macular degeneration.}, journal = {Invest Ophthalmol Vis Sci}, volume = {52}, year = {2011}, month = {2011 Nov 25}, pages = {9195-206}, abstract = {

PURPOSE: Determining the relationships between phenotype and genotype of many disorders can improve clinical diagnoses, identify disease mechanisms, and enhance therapy. Most genetic disorders result from interaction of many genes that obscure the discovery of such relationships. The hypothesis for this study was that image analysis has the potential to enable formalized discovery of new visible phenotypes. It was tested in twins affected with age-related macular degeneration (AMD).

METHODS: Fundus images from 43 monozygotic (MZ) and 32 dizygotic (DZ) twin pairs with AMD were examined. First, soft and hard drusen were segmented. Then newly defined phenotypes were identified by using drusen distribution statistics that significantly separate MZ from DZ twins. The ACE model was used to identify the contributions of additive genetic (A), common environmental (C), and nonshared environmental (E) effects on drusen distribution phenotypes.

RESULTS: Four drusen distribution characteristics significantly separated MZ from DZ twin pairs. One encoded the quantity, and the remaining three encoded the spatial distribution of drusen, achieving a zygosity prediction accuracy of 76\%, 74\%, 68\%, and 68\%. Three of the four phenotypes had a 55\% to 77\% genetic effect in an AE model, and the fourth phenotype showed a nonshared environmental effect (E model).

CONCLUSIONS: Computational discovery of genetically determined features can reveal quantifiable AMD phenotypes that are genetically determined without explicitly linking them to specific genes. In addition, it can identify phenotypes that appear to result predominantly from environmental exposure. The approach is rapid and unbiased, suitable for large datasets, and can be used to reveal unknown phenotype-genotype relationships.

}, keywords = {Aged, 80 and over, Diseases in Twins, Female, Genetic Predisposition to Disease, Genotype, Humans, Macular Degeneration, Male, Phenotype, Registries, Retinal Drusen, Twins, Dizygotic, Twins, Monozygotic}, issn = {1552-5783}, doi = {10.1167/iovs.10-6793}, author = {Quellec, Gw{\'e}nol{\'e} and Russell, Stephen R and Seddon, Johanna M and Reynolds, Robyn and Scheetz, Todd and Mahajan, Vinit B and Stone, Edwin M and Abr{\`a}moff, Michael D} } @article {147, title = {Mouse eye enucleation for remote high-throughput phenotyping.}, journal = {Journal of visualized experiments : JoVE}, year = {2011}, month = {2011}, abstract = {

The mouse eye is an important genetic model for the translational study of human ophthalmic disease. Blinding diseases in humans, such as macular degeneration, photoreceptor degeneration, cataract, glaucoma, retinoblastoma, and diabetic retinopathy have been recapitulated in transgenic mice.(1-5) Most transgenic and knockout mice have been generated by laboratories to study non-ophthalmic diseases, but genetic conservation between organ systems suggests that many of the same genes may also play a role in ocular development and disease. Hence, these mice represent an important resource for discovering new genotype-phenotype correlations in the eye. Because these mice are scattered across the globe, it is difficult to acquire, maintain, and phenotype them in an efficient, cost-effective manner. Thus, most high-throughput ophthalmic phenotyping screens are restricted to a few locations that require on-site, ophthalmic expertise to examine eyes in live mice. (6-9) An alternative approach developed by our laboratory is a method for remote tissue-acquisition that can be used in large or small-scale surveys of transgenic mouse eyes. Standardized procedures for video-based surgical skill transfer, tissue fixation, and shipping allow any lab to collect whole eyes from mutant animals and send them for molecular and morphological phenotyping. In this video article, we present techniques to enucleate and transfer both unfixed and perfusion fixed mouse eyes for remote phenotyping analyses.

}, keywords = {Animals, Eye Enucleation, High-Throughput Screening Assays, Mice, Mice, Transgenic, Phenotype, Tissue Fixation}, author = {Mahajan, Vinit B and Skeie, Jessica M and Assefnia, Amir H and Mahajan, Maryann and Tsang, Stephen H} } @article {149, title = {Mutations in prickle orthologs cause seizures in flies, mice, and humans.}, journal = {American journal of human genetics}, volume = {88}, year = {2011}, month = {2011 Feb 11}, pages = {138-49}, abstract = {

Epilepsy is heritable, yet few causative gene mutations have been identified, and thus far no human epilepsy gene mutations have been found to produce seizures in invertebrates. Here we show that mutations in prickle genes are associated with seizures in humans, mice, and flies. We identified human epilepsy patients with heterozygous mutations in either PRICKLE1 or PRICKLE2. In overexpression assays in zebrafish, prickle mutations resulted in aberrant prickle function. A seizure phenotype was present in the Prickle1-null mutant mouse, two Prickle1 point mutant (missense and nonsense) mice, and a Prickle2-null mutant mouse. Drosophila with prickle mutations displayed seizures that were responsive to anti-epileptic medication, and homozygous mutant embryos showed neuronal defects. These results suggest that prickle mutations have caused seizures throughout evolution.

}, keywords = {Animals, Blotting, Western, Brain, Calcium, Carrier Proteins, DNA-Binding Proteins, Drosophila melanogaster, Drosophila Proteins, Embryo, Nonmammalian, Epilepsies, Myoclonic, Female, Heterozygote, Humans, Immunoenzyme Techniques, In Situ Hybridization, Male, Mice, Mice, Knockout, Mutation, Nerve Tissue Proteins, Phenotype, Reverse Transcriptase Polymerase Chain Reaction, RNA, Messenger, Seizures, Tumor Suppressor Proteins, Zebrafish, Zebrafish Proteins}, author = {Tao, Hirotaka and Manak, J Robert and Sowers, Levi and Mei, Xue and Kiyonari, Hiroshi and Abe, Takaya and Dahdaleh, Nader S and Yang, Tian and Wu, Shu and Chen, Shan and Fox, Mark H and Gurnett, Christina and Montine, Thomas and Bird, Thomas and Shaffer, Lisa G and Rosenfeld, Jill A and McConnell, Juliann and Madan-Khetarpal, Suneeta and Berry-Kravis, Elizabeth and Griesbach, Hilary and Saneto, Russell P and Scott, Matthew P and Antic, Dragana and Reed, Jordan and Boland, Riley and Ehaideb, Salleh N and El-Shanti, Hatem and Mahajan, Vinit B and Ferguson, Polly J and Axelrod, Jeffrey D and Lehesjoki, Anna-Elina and Fritzsch, Bernd and Slusarski, Diane C and Wemmie, John and Ueno, Naoto and Bassuk, Alexander G} } @article {173, title = {A new macular dystrophy with anomalous vascular development, pigment spots, cystic spaces, and neovascularization.}, journal = {Archives of ophthalmology}, volume = {127}, year = {2009}, month = {2009 Nov}, pages = {1449-57}, abstract = {

To clinically phenotype an inherited macular dystrophy with peculiar intraretinal pigment spots, cysts, and hemorrhage in a 24-year-old female proband and her family.

}, keywords = {Adolescent, Adult, Amblyopia, Child, Child, Preschool, Cysts, Electroretinography, Female, Fluorescein Angiography, Humans, Macular Degeneration, Male, Middle Aged, Pedigree, Phenotype, Retinal Hemorrhage, Retinal Neovascularization, Retinal Pigment Epithelium, Retinal Vessels, Strabismus, Tomography, Optical Coherence, Visual Acuity, Young Adult}, author = {Mahajan, Vinit B and Russell, Stephen R and Stone, Edwin M} }