{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,3]],"date-time":"2026-06-03T14:56:05Z","timestamp":1780498565881,"version":"3.54.1"},"reference-count":35,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2025,4,23]],"date-time":"2025-04-23T00:00:00Z","timestamp":1745366400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Scientific Grant Agency of the Slovak Republic","award":["1\/0240\/25"],"award-info":[{"award-number":["1\/0240\/25"]}]},{"name":"Scientific Grant Agency of the Slovak Republic","award":["008UVLF-4\/2023"],"award-info":[{"award-number":["008UVLF-4\/2023"]}]},{"name":"Cultural and Educational Grant Agency of the Ministry of Education, Research, Development, and Youth of the Slovak Republic","award":["1\/0240\/25"],"award-info":[{"award-number":["1\/0240\/25"]}]},{"name":"Cultural and Educational Grant Agency of the Ministry of Education, Research, Development, and Youth of the Slovak Republic","award":["008UVLF-4\/2023"],"award-info":[{"award-number":["008UVLF-4\/2023"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Genes"],"abstract":"<jats:p>Background: Two hereditary eye disorders that are frequently observed in Collies and related breeds are Collie Eye Anomaly (CEA) and Progressive Retinal Atrophy (PRA). The main symptom of CEA is choroidal hypoplasia. It is associated with a 7.8 kb deletion in intron 4 of the NHEJ1 gene located on chromosome CFA7. Rod\u2013cone dysplasia 3 (RCD3), an early-onset form of PRA, is associated with mutations in the PDE6A gene. Methods: Molecular diagnostic techniques were used in this study to identify genetic mutations linked to CEA and RCD3-type PRA in a subset of dog breeds. Australian Shepherds (n = 29), Border Collies (n = 9), Longhaired Collies (n = 27), and Shetland Sheepdogs (n = 10) provided a total of 75 DNA samples. Samples were collected by buccal swab or blood draw, and PCR and real-time PCR methods were used for processing. Results: Of the dogs in the studied breeds, 31 had the NHEJ1 gene mutation linked to CEA. Among these, 15 were homozygous recessive (affected), while 16 were heterozygous (carriers). None of the samples had any mutations in the PDE6A gene associated with RCD3-type PRA. Conclusions: Effective identification of carriers and affected individuals for CEA was made possible by PCR-based genetic testing, confirming its value in early diagnosis and breed control. Although the RCD3 form of PRA has not been previously reported in Collies or Australian Shepherds, it was included in our analysis due to the genetic relatedness among herding breeds and the potential presence of undetected carriers resulting from historical crossbreeding.<\/jats:p>","DOI":"10.3390\/genes16050474","type":"journal-article","created":{"date-parts":[[2025,4,23]],"date-time":"2025-04-23T06:38:37Z","timestamp":1745390317000},"page":"474","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Analysis of Selected Eye Disorders in a Group of Predisposed Breeds of Dogs: Molecular Diagnostics of Collie Eye Anomaly and Progressive Retinal Atrophy"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0009-0001-6174-2820","authenticated-orcid":false,"given":"Jaroslav","family":"Bu\u010dan","sequence":"first","affiliation":[{"name":"Department of Biology and Physiology, University of Veterinary Medicine and Pharmacy in Ko\u0161ice, Komensk\u00e9ho 73, 04181 Ko\u0161ice, Slovakia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Be\u00e1ta","family":"Hole\u010dkov\u00e1","sequence":"additional","affiliation":[{"name":"Department of Biology and Physiology, University of Veterinary Medicine and Pharmacy in Ko\u0161ice, Komensk\u00e9ho 73, 04181 Ko\u0161ice, Slovakia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Martina","family":"Gald\u00edkov\u00e1","sequence":"additional","affiliation":[{"name":"Department of Biology and Physiology, University of Veterinary Medicine and Pharmacy in Ko\u0161ice, Komensk\u00e9ho 73, 04181 Ko\u0161ice, Slovakia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8137-1684","authenticated-orcid":false,"given":"Jana","family":"Halu\u0161kov\u00e1","sequence":"additional","affiliation":[{"name":"Department of Biology and Physiology, University of Veterinary Medicine and Pharmacy in Ko\u0161ice, Komensk\u00e9ho 73, 04181 Ko\u0161ice, Slovakia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-3396-7663","authenticated-orcid":false,"given":"Viera","family":"Schwarzbacherov\u00e1","sequence":"additional","affiliation":[{"name":"Department of Biology and Physiology, University of Veterinary Medicine and Pharmacy in Ko\u0161ice, Komensk\u00e9ho 73, 04181 Ko\u0161ice, Slovakia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,4,23]]},"reference":[{"key":"ref_1","unstructured":"(2025, April 05). OMIA\u2014Online Mendelian Inheritance in Animals. Available online: https:\/\/www.omia.org\/home\/."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"441","DOI":"10.1007\/s00439-019-01999-6","article-title":"Natural models for retinitis pigmentosa: Progressive retinal atrophy in dog breeds","volume":"138","author":"Bunel","year":"2019","journal-title":"Hum. Gen."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"476","DOI":"10.1007\/s00335-011-9348-0","article-title":"The function of dog models in developing gene therapy strategies for human health","volume":"22","author":"Nowend","year":"2011","journal-title":"Mamm. Genome"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"48","DOI":"10.2478\/fv-2022-0026","article-title":"Hereditary eye diseases in German shepherd dog","volume":"66","year":"2022","journal-title":"Fol. Vet."},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Balicki, I., Goleman, M., and Balicka, A. (2021). Ocular abnormalities in Polish Hunting Dogs. PLoS ONE, 16.","DOI":"10.1371\/journal.pone.0258636"},{"key":"ref_6","first-page":"145","article-title":"Harnessing CRISPR-CAS9 gene editing for the eradication of inherited retinal diseases in purebred dogs: A path to preservation and health","volume":"12","author":"Ali","year":"2024","journal-title":"J. Anim. Health Prod."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"346","DOI":"10.17221\/259\/2009-CJAS","article-title":"Simplified PCR analysis of a mutation in the NHEJ1 gene causing ollie eye anomaly in some dog breeds","volume":"55","author":"Stratil","year":"2010","journal-title":"Czech J. Anim. Sci."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"708","DOI":"10.1177\/104063871002200506","article-title":"A Novel Rapid Genotyping Technique for Collie Eye Anomaly: SYBR Green\u2013Based Real-Time Polymerase Chain Reaction Method Applicable to Blood and Saliva Specimens on Flinders Technology Associates Filter Paper","volume":"22","author":"Chang","year":"2010","journal-title":"J. Vet. Diagn. Investig."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"357","DOI":"10.1111\/j.1463-5224.2005.00417.x","article-title":"Collie eye anomaly in a mixed-breed dog","volume":"8","author":"Rampazzo","year":"2005","journal-title":"Vet. Ophthalmol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"354","DOI":"10.1136\/vr.143.13.354","article-title":"Collie eye anomaly in the Lancashire heeler","volume":"143","author":"Bedford","year":"1998","journal-title":"Vet. Rec."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"e26","DOI":"10.1002\/vro2.26","article-title":"Genotypic and allelic frequency of a mutation in the NHEJ1 gene associated with collie eye anomaly in dogs in Italy","volume":"9","author":"Marelli","year":"2022","journal-title":"Vet. Rec. Open"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"801","DOI":"10.1167\/iovs.08-2562","article-title":"Characterization of a Canine Model of Autosomal Recessive Retinitis Pigmentosa due to a PDE6A Mutation","volume":"50","author":"Tuntivanich","year":"2009","journal-title":"Investig. Ophthalmol. Vis. Sci."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"445","DOI":"10.1186\/1297-9686-35-5-445","article-title":"Analysis of PDE6D and PDE6G genes for generalised progressive retinal atrophy (gPRA) mutations in dogs","volume":"35","author":"Dekomien","year":"2003","journal-title":"Genet. Sel. Evol."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"861","DOI":"10.3109\/02713689309020391","article-title":"Confirmation of the rod cGMP phosphodiesterase \u03b2 subunit (PDE\u03b2) nonsense mutation in affected rcd-1 Irish setters in the UK and development of a diagnostic test","volume":"12","author":"Clements","year":"1993","journal-title":"Curr. Eye Res."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"441","DOI":"10.1016\/0197-0186(80)90078-9","article-title":"Cyclic GMP phosphodiesterase activator: Involvement in a hereditary retinal degeneration","volume":"1","author":"Chader","year":"1980","journal-title":"Neurochem. Int."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"844","DOI":"10.2460\/ajvr.2000.61.844","article-title":"Development and use of a polymerase chain reaction-based diagnostic test for the causal mutation of progressive retinal atrophy in Cardigan Welsh Corgis","volume":"61","author":"Zhu","year":"2000","journal-title":"Am. J. Vet. Res."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"1562","DOI":"10.1101\/gr.6772807","article-title":"Breed relationships facilitate fine-mapping studies: A 7.8-kb deletion cosegregates with Collie eye anomaly across multiple dog breeds","volume":"17","author":"Parker","year":"2007","journal-title":"Genome Res."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"86","DOI":"10.1016\/S0888-7543(03)00078-8","article-title":"Linkage mapping of the primary disease locus for collie eye anomaly","volume":"82","author":"Lowe","year":"2003","journal-title":"Genomics"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"345","DOI":"10.17221\/8381-VETMED","article-title":"Collie eye anomaly: A review","volume":"60","author":"Palanova","year":"2015","journal-title":"Vet. Med."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"66","DOI":"10.1080\/01652176.1981.9693799","article-title":"Collie eye anomaly in Collies in the Netherlands","volume":"3","author":"Stades","year":"1981","journal-title":"Vet. Q."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"263","DOI":"10.1136\/vr.111.12.263","article-title":"Collie eye anomaly in the United Kingdom","volume":"111","author":"Bedford","year":"1982","journal-title":"Vet. Rec."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"597","DOI":"10.1024\/0036-7281.151.12.597","article-title":"Collie eye anomaly in Switzerland","volume":"151","author":"Spiess","year":"2009","journal-title":"Schweiz. Arch. Tierheilkd."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"132","DOI":"10.14202\/vetworld.2022.132-139","article-title":"A novel multiplex polymerase chain reaction assay for the genotypic survey of the non-homologous end-joining factor 1 gene associated with Collie eye anomaly in Thailand","volume":"15","author":"Lerdkrai","year":"2022","journal-title":"Vet. World"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"19","DOI":"10.1111\/j.1463-5224.2007.00486.x","article-title":"A retrospective evaluation of congenital ocular defects in Australian Shepherd dogs in Australia","volume":"10","author":"Munyard","year":"2007","journal-title":"Vet. Ophthalmol."},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Kucharczyk, N., Cislo-Pakuluk, A., and Bedford, P. (2019). Collie eye anomaly in Australian Kelpie dogs in Poland. BMC Vet. Res., 15.","DOI":"10.1186\/s12917-019-2143-y"},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Majchrakova, Z., Hrckova Turnova, E., Bielikova, M., Turna, J., and Dudas, A. (2023). The incidence of genetic disease alleles in Australian Shepherd dog breed in European countries. PLoS ONE, 18.","DOI":"10.1371\/journal.pone.0281215"},{"key":"ref_27","doi-asserted-by":"crossref","unstructured":"Clark, J.A., Anderson, H., Donner, J., Pearce-Kelling, S., and Ekenstedt, K.J. (2023). Global Frequency Analyses of Canine Progressive Rod-Cone Degeneration\u2013Progressive Retinal Atrophy and Collie Eye Anomaly Using Commercial Genetic Testing Data. Genes, 14.","DOI":"10.3390\/genes14112093"},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Carrigan, M., Duignan, E., Malone, C., Stephenson, K., Saad, T., McDermott, C., Green, A., Keegan, D., Humphries, P., and Kenna, P.F. (2016). Panel-Based Population Next-Generation Sequencing for Inherited Retinal Degenerations. Sci. Rep., 6.","DOI":"10.1038\/srep33248"},{"key":"ref_29","doi-asserted-by":"crossref","unstructured":"Lukovic, D., Artero Castro, A., Delgado, A., Bernal, M.A.M., Pelaez, A.D., Lloret, R.P., Espejo, R.P., Kamenarova, K., S\u00e1nchez, L.F., and Cuenca, N. (2015). Human iPSC derived disease model of MERTK-associated retinitis pigmentosa. Sci. Rep., 5.","DOI":"10.1038\/srep12910"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"6","DOI":"10.1167\/tvst.7.4.6","article-title":"Inherited Retinal Degenerations: Current Landscape and Knowledge Gaps","volume":"7","author":"Duncan","year":"2018","journal-title":"Trans. Vis. Sci. Tech."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"274","DOI":"10.1038\/ejhg.2012.172","article-title":"Next-generation sequencing (NGS) as a diagnostic tool for retinal degeneration reveals a much higher detection rate in early-onset disease","volume":"21","author":"Shanks","year":"2012","journal-title":"Eur. J. Hum. Genet."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"195","DOI":"10.1210\/er.2013-1053","article-title":"Clinical and Molecular Genetics of the phosphodiesterases (PDES)","volume":"35","author":"Azevedo","year":"2013","journal-title":"Endocr. Rev."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"e77","DOI":"10.1002\/vro2.77","article-title":"Genotypic and allelic frequencies of progressive rod-cone degeneration and other main variants associated with progressive retinal atrophy in Italian dogs","volume":"10","author":"Ghilardi","year":"2023","journal-title":"Vet. Rec. Open"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"109","DOI":"10.1111\/vop.12932","article-title":"Development of retinal bullae in dogs with progressive retinal atrophy","volume":"25","author":"Marinho","year":"2021","journal-title":"Vet. Ophthal."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"126","DOI":"10.1111\/vop.12122","article-title":"Genetic screening for PRA-associated mutations in multiple dog breeds shows that PRA is heterogeneous within and between breeds","volume":"17","author":"Downs","year":"2014","journal-title":"Vet. Ophthalmol."}],"container-title":["Genes"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2073-4425\/16\/5\/474\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T17:19:57Z","timestamp":1760030397000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2073-4425\/16\/5\/474"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,4,23]]},"references-count":35,"journal-issue":{"issue":"5","published-online":{"date-parts":[[2025,5]]}},"alternative-id":["genes16050474"],"URL":"https:\/\/doi.org\/10.3390\/genes16050474","relation":{},"ISSN":["2073-4425"],"issn-type":[{"value":"2073-4425","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,4,23]]}}}