Genetic Defects of the Eye
Which inherited eye defects occur in the Siberian Husky?
Although there are many possible eye defects, only three are of current concern in the Siberian. These are hereditary or
juvenile cataracts, corneal dystrophy, and progressive retinal atrophy. Each disorder is present in a different portion of the eye,
and will occur in any eye color. Eye defects in the Siberian Husky are serious and should not be understated or overlooked.
What are hereditary cataracts & how are they transmitted?
Hereditary or juvenile cataracts are manifested by opacity in the lens of a young dog as early as 3 months of age. These cataracts
are different from the non-hereditary cataracts affecting aged or senior dogs. The function of the lens of the eye is to focus the rays
of light so that they form an image on the retina. An opacity or cataract on the lens causes less light to enter the eye and sight can
be diminished. A cataract can cause a mild decrease in eyesight to complete blindness in severe cases. Cataracts can further be
classified by location and stage of development. It is not uncommon for a cataract to develop in one eye months before the
other eye shows the effects of the disease.
What is corneal dystrophy?
Corneal dystrophy affects the cornea or the outer transparent portion of the eyeball. In most cases, Siberian Huskies with this
disorder have an abnormal collection of lipids in the clear cornea of the eye which results in a hazy or crystalline opacity.
Ophthalmologists describe the location of the opacity as anterior, mid, or deep stromal. The Siberian Husky is prone to
deep stromal dystrophy which involves triglyceride deposits. Annular dystrophy also occurs and appears as a doughnut
shaped opacity in the peripheral cornea. Corneal dystrophy is usually seen in young adult dogs and may affect females more than males.
Vision is seldom affected and no effective therapy for the condition exists at this time. Recent genetic tests are suggesting that a
recessive gene with variant expression transmits this disorder.
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