Ocular albinism with mutation in GPR143: Findings in wide-field autofluorescence and optical coherence tomography

M J Montoya Delgado1, M C Astiazarán1, F Casanova Imken1

  • 1Departamento de Retina y Vítreo, Fundación Hospital Nuestra Señora de la Luz, Ciudad de México, México.

Insights

X-linked ocular albinism, a common genetic condition, was diagnosed in a boy and his mother. Genetic testing identified a GPR143 gene mutation, confirming the diagnosis and revealing novel retinal findings in the mother.

Area of Science:

  • Ophthalmology
  • Genetics
  • Medical Imaging

Background:

  • Ocular albinism linked to X (XLOA) is the most frequent genetic variant of ocular albinism.
  • Patients present with nystagmus and low vision from birth.
  • Ocular findings include iris hypopigmentation, fundus hypopigmentation, foveal hypoplasia, and reduced visual acuity.

Observation:

  • A 12-year-old boy presented with congenital nystagmus and low vision.
  • His mother reported lifelong low vision, with recent worsening.
  • Clinical examination revealed iris hypopigmentation, choroidal fundus, foveal hypoplasia, and absence of macular hypo-autofluorescence in the child.
  • The mother showed macular pigmentary changes, peripheral retinal hyperpigmented spots, and outer retinal layer cavitation in the fovea.

Findings:

  • Genetic sequencing identified a GPR143 gene mutation, with the son being hemizygous and the mother heterozygous.
  • X-linked ocular albinism was diagnosed.
  • This case presents a novel finding of outer retinal layer cavitation in a heterozygous carrier, not previously reported.

Implications:

  • This study expands the understanding of clinical manifestations in female carriers of XLOA.
  • Highlights the importance of advanced imaging techniques like optical coherence tomography in diagnosing subtle retinal changes.
  • Emphasizes the role of genetic testing in confirming XLOA and facilitating genetic counseling.

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