Hereditary Cataracts (HC) are defined as the clouding of the lens of the eye. Cataracts impair vision and, if progressive, may lead to total blindness because the lens normally focuses light on the retina to enable vision. Cataracts can develop in one eye or in both eyes due to the aging process, underlying diseases, injury or a genetic defect. In the Boston Terrier and the Staffordshire Bull Terrier, a genetic defect in the HSF4 gene is associated with HC.
Cataracts may start forming early onset before 1 year of age or late onset after 2 years of age with variable rate of progression and impaired vision.
The late onset form of HC in Boston Terriers is not associated with the HSF4 mutation.
Test specific information
Symptoms will develop at a young age. Within a few hours to a maximum of several weeks after birth, the characteristics that go with these genetic effects will become visible.
The Turnaround Time (TAT) depends on various factors, such as the shipment time of your sample to the test location, the test method(s) and whether the tests are performed completely or partially by a Partner Lab or Patent owner.
The TAT of tests performed at our facilities is normally 10 working days after receipt of the sample at the testing laboratory (VHL, VHP or Certagen). For tests performed by a Partner Laboratory (so-called "partner lab test") or patent owner, the TAT is at least 20 working days after receipt of your sample. Because the shipment time to our Partner Labs or patent owner may vary due to factors we cannot influence, the mentioned 20 working days are therefore an estimate.
Sometimes it is necessary to re-run your sample. We call this a retest. In that case, the TAT will of course be extended.
Location of disease or trait
This disease mainly affects vision, and may result in blindness.
This DNA test is available for the following breeds: Boston Terrier, French Bulldog, Staffordshire Bull Terrier. Additional information is available in the Frequently Asked Questions (FAQ).
For this DNA test we accept the following materials: Blood EDTA, Blood Heparin, Semen, Swab, Tissue. Please contact Dr. Van Haeringen Laboratorium if you wish to submit other material as listed.
An animal can be free and has in that situation two healthy alleles. When used in breeding this animal will not become ill due to the disease. It cannot spread the disease in the population.
An animal can be carrier and has in that situation one healthy and one disease allele. When used in breeding 50 percent of the offspring will receive the disease allele. Carriers will not become ill.
An animal can be affected and has in that situation two disease alleles. When used in breeding all offspring will also receive the disease allele. Affected will become ill.
This genetic factor is inherited in an autosomal, recessive, mode. This means, that the individual can be free of the disease (homozygote normal), affected (homozygous affected) or carrier (heterozygous).
Carriers may spread the mutation in a population without showing symptoms themselves. Because of this, it is extremely important to identify carriers correctly to prevent spreading of a mutation.
Severity of Disease