In affected dogs the fibres supporting the lens breakdown or disintegrate, causing the lens to fall into the wrong position within the eye. If the lens falls into the anterior chamber of the eye, glaucoma and loss of vision can quickly result, accompanied by pain.  Lens luxation may also arise from trauma and as yet, unidentified genetic mutations. 

Interpreting DNA test results for PLL

Clear dogs have no copies of the mutant gene responsible for the condition and will neither develop the condition nor pass the gene on to their offspring.

Carrier dogs have one copy of the normal gene and one copy of the mutant gene; these dogs have a very low risk of developing PLL (estimated between 2% – 20% of carriers will develop the condition, percentage is nearer to 2% than 20%). Advice is all carriers have their eyes examined by a veterinary ophthalmologist under the BVA/KC Eye Scheme* every 6- 12 months, from the age of two years.

Affected dogs have two copies of the mutant gene that causes the condition and will develop the disease.  Advice is all affected dogs have their eyes examined by a veterinary ophthalmologist under the BVA/KC Eye Scheme* every 6 months, from the age of 18 months, so the clinical signs of PLL are detected as early as possible.

Breeding Advice

Allowing only CLEAR dogs to breed could have a devastating effect on breed diversity and substantially increase the likelihood of new inherited diseases emerging.  GENETICALLY AFFECTED and CARRIER dogs can be bred with, but should only be bred to DNA tested, CLEAR dogs.
*Eye testing under the BVA/KC Eye Scheme is offered at a reduce cost for dogs aged 8 years and over.

Information provided by Dr Sarah Broadberry – Kennel Club Breed Health Representative

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