30 Questions
Which of the following diseases can result in retinal changes and are considered in the text?
Neuronal ceroid lipofuscinosis
What type of changes were observed in the choriocapillaris?
Dystrophic changes
Where were the areas of geographic atrophy found?
Midperipheral and peripheral fundus
What is the mode of inheritance for the defect?
No mode of inheritance established
Which of the following diseases are NOT considered in the text?
Gangliosidosis
Which retinopathy is characterized by multifocal red or brown tapetal discoloration and no vision loss?
Swedish Vallhund retinopathy
What is the prevalence of Swedish Vallhund retinopathy in the breed?
34.9%
Which gene is associated with increased levels of mRNA in affected retina of Swedish Vallhunds with retinopathy?
MERTK
Which retinopathy is characterized by a rapid nystagmus, reduced PLRs, and accumulation of inclusion bodies in the RPE cells?
RPE65-mutant retinopathy
Which retinopathy shows retinal thinning, night blindness, severe daytime vision problems, and a severe reduction in ERG amplitudes in its most advanced stage?
Swedish Vallhund retinopathy
Which term is commonly used to describe the retinopathy caused by RPE65 mutation in Briards?
Congenital stationary night blindness
What is the main role of RPE65 in the visual cycle?
To act as a retinoid isomerase
What is the consequence of a lack of functional RPE65?
Reduced vision in bright lighting conditions
Which mutation is most commonly associated with Leber congenital amaurosis in humans?
RPE65 mutation
What has been approved as a treatment for Leber congenital amaurosis due to RPE65 mutations in the United States?
Gene therapy
Which breed of dog was found to have a missense mutation (c.C1270T; p.Arg424Trp) in the CNGA3 gene causing day blindness?
German Shepherd Dog
What amino acid is changed by the missense mutation (c.C1270T; p.Arg424Trp) in the CNGA3 gene in German Shepherd Dogs?
Arginine
What type of mutation was found in the Labrador Retrievers with day blindness?
3 bp deletion
What amino acid is removed by the 3 bp deletion (c.1931_ 1933delTGG) in the CNGA3 gene in Labrador Retrievers?
Valine
In which breed of dog was a recessively inherited congenital stationary night blindness (CSNB) reported?
Beagles
Which breed has been reported to have an unusually high frequency of Retinal Pigment Epithelial Dystrophy (RPED)?
Briards
What is the initial visual impairment experienced by dogs with RPED?
Problems seeing stationary objects in brighter light
Which breed has a breed-related condition consisting of RPED and neurologic dysfunction associated with low circulatory levels of vitamin E?
English Cocker Spaniels
What is the recommended oral tocopherol supplementation for English Cocker Spaniels diagnosed with vitamin E deficiency?
600-900 IU twice daily
What is the characteristic appearance of retinal lesions in the Chinese Crested Dog with pigmentary chorioretinopathy?
Darkly pigmented with a light center
Which gene is responsible for the late-onset retinopathy in Labrador Retrievers?
ABCA4
What is the function of ABCA4 in the visual cycle?
Transport of N-retinylidene-phosphatidylethanolamine and phosphatidylethanolamine out of the lumen
Which subunits make up the cGMP-gated channel in the outer segment cell membrane of cone photoreceptors?
CNGB3 and CNGA3
Which breed of dog has the CNGB3 mutation that causes achromatopsia?
Alaskan Malamute
What treatment has been successful in restoring cone function in younger dogs with achromatopsia?
Both gene therapy and CNTF treatment
Quiz: Can You Identify Mutations Causing Day Blindness in Dogs? Test your knowledge on CNGA3 mutations in German Shepherd Dogs and Labrador Retrievers with day blindness. Can you recognize the specific genetic changes responsible for this condition? Challenge yourself with this quiz and become an expert in canine genetics.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
