Kloudknine Australia

Staffordshire Bull Terrier Health Information

L-2-Hydroxyglutaric Aciduria (L2HGA) is a neurometabolic disorder;
it causes progressive deterioration of the central nervous system function.
The disease is characterized by elevated levels of L-2-hydroxyglutaric acid in urine, plasma and
cerebrospinal fluid.
This produces neurological defects including psychomotor retardation, altered behaviour, seizures and

Hereditary Cataracts (HC) are a clouding of the lens of the eye caused by a breakdown of tissue in the
eye. This condition generally results in an inability to see clearly and can cause total blindness. In canines,
cataracts are often familial; this type is known as Hereditary Cataracts. A mutation in the HSF4 gene causes
this type of cataracts in several breeds of dogs. In this case, the dog is typically affected bilaterally, in that
both eyes are affected by the cataracts. The cataracts associated with HSF4 also occur in the posterior
region of the lens. They usually start by being small and grow progressively, though the speed of growth is
highly variable. Some cataracts will grow so slowly that the dog’s vision remains relatively clear, while
others will grow such a way that the dog will quickly go blind. Corrective surgery is possible, though it is
costly and is not always effective.

A mutation of the HSF4 gene is linked to a form of Hereditary Cataracts in Australian Shepherds. This
mutation affects Aussies differently then Boston Terriers, French Bulldogs and Staffordshire Bull Terriers
in that the disease is dominant but not completely penetrant. This means that only one copy of the mutation is
necessary to predispose a dog to the disease. However, incomplete penetrance means that a dog that has
this mutation will not always develop HC. Research suggests that the mutation makes a dog 12 times more
likely to develop posterior bilateral cataracts at some point in their lifetime. It is likely that a secondary
gene interaction occurs in the small percentage of dogs possessing the HC mutation but does not develop
cataracts. This interaction is not yet understood.

It should also be noted that not all cataracts are hereditary. Cataracts can also be caused by old age or
injury. Also, cataracts that occur in different regions of the lens can also be familial, however, are not
attributed to this gene mutation.

Scroll to Top