Test Detail

Hereditary ocular disease of the Shar Pei in which primary open-angle glaucoma and lens luxation coexist, caused by the same variant of the ADAMTS17 gene. The defect in the extracellular matrix of the zonules and of the iridocorneal angle reduces aqueous humour drainage and favours lens instability, with increased intraocular pressure, pain and blindness. It is inherited in an autosomal recessive manner.

Affected breed: Shar Pei (Chinese). No reliable large-scale population frequencies are published; the disease is known in the breed and a genetic test is available for the Shar Pei.

- Test Shar Pei breeding animals with the ADAMTS17 test (POAG/PLL)\n- Do not mate two carriers: 25% risk of affected homozygotes\n- A carrier may be mated with a clear dog; offspring intended for breeding must be tested\n- Prioritise breeding dogs that will not develop the disease as the main objective, and reduce the allele frequency as a long-term objective\n- Exclude affected animals from breeding and monitor them clinically at an early stage

It is difficult to differentiate clinically whether lens luxation is primary or secondary to glaucoma, so in practice both processes are considered together as POAG/PLL in the breed. Differential diagnosis with glaucoma secondary to uveitis or tumour and with traumatic luxation. Gonioscopy and biomicroscopy guide; confirmation is molecular. Periodic ophthalmological monitoring of homozygotes allows early interventions and a better visual prognosis.

1. Oliver JAC, Rustidge S, Pettitt L, et al. (2018) Evaluation of ADAMTS17 in Chinese Shar-Pei with primary open-angle glaucoma, primary lens luxation, or both. Am J Vet Res 79:98-106. PMID: 29287154
2. Lazarus JA, Pickett JP, Champagne ES, et al. (1998) Primary lens luxation in the Chinese Shar Pei: clinical and hereditary characteristics. Vet Ophthalmol 1(2-3):101-107. PMID: 11397217