Primary congenital glaucoma / PCG (LTBP2-related) - Siamese

Primary congenital glaucoma in Siamese cats

This genetic test detects the LTBP2 duplication c.1449_1452dup that causes primary congenital glaucoma. The condition is also known as PCG, primary glaucoma 3 or glaucoma 3, primary congenital. A frameshift in LTBP2 disrupts normal development of the drainage structures in the anterior segment of the eye.

Clinical picture and recognition

Affected kittens can develop elevated intraocular pressure, enlarged eyes and optic nerve damage at an early age. The disorder matters for Siamese and related lines because two copies of the variant cause the disease.

Why this test is useful

• The result distinguishes clear cats, carriers and genetically affected cats.
• Breeders can avoid carrier-to-carrier matings and prevent high-risk combinations deliberately.
• The result helps explain eye problems in related lines more quickly at the genetic level.

PCG is inherited as autosomal recessive: one copy means carrier status, while two copies cause primary congenital glaucoma.