PRPH2 – fundus albipunctatus

A single pediatric case of fundus albipunctatus was reported in a patient with a heterozygous PRPH2 missense variant, c.806C>G (p.Thr269Arg), presenting with macular edema and visual impairment (PMID:38860019). No additional affected family members or segregation data were described, and the inheritance was consistent with an autosomal dominant pattern.

Functional studies of the rds (Prph2) gene in a transgenic mouse model demonstrate that introduction of wild-type Prph2 under the opsin promoter fully rescues photoreceptor morphology and prevents degeneration in homozygous rds mutants, confirming the critical role of PRPH2 in photoreceptor outer segment structure (PMID:1385966).

Overall, the evidence linking PRPH2 to fundus albipunctatus is limited due to a single reported proband without segregation, but functional concordance in animal models supports pathogenicity. Clinically, PRPH2 genetic testing may be considered in unexplained cases of fundus albipunctatus, particularly when macular edema is present.

References

• Oxford medical case reports • 2024 • Pigmentary retinal dystrophy associated with peroxisome biogenesis disorder-Zellweger syndrome spectrum. PMID:38860019
  
• Neuron • 1992 • Complete rescue of photoreceptor dysplasia and degeneration in transgenic retinal degeneration slow (rds) mice. PMID:1385966

Evidence Based Scoring (AI generated)