Identification of a novel CRB1 variant in a compound heterozygous state in a patient with CRB1-associated maculopathy and foveal retinoschisis

ABSTRACT

Purpose

To report a novel CRB1 variant responsible for autosomal recessive foveal retinoschisis and its associated clinical and electrophysiological data.

Methods

A case report.

Results

A 15-year-old boy has foveal retinoschisis similar to those seen in X-linked retinoschisis (XLRS). During follow-up, we observed the co-existence of foveoschitic changes and parafoveal macular atrophy. Molecular genetic testing identified compound heterozygous variants in the CRB1 gene, including a novel variant, c.3878 G > A, predicted to disrupt the normal translation of CRB1 and a previously reported likely pathogenic mutation, c.498_506del. Full-field electroretinograms (ERG) were normal but multifocal ERG showed focal reduced waveform amplitude corresponding to the area of atrophy.

Conclusions

A novel missense variant existing in a compound heterozygous state was identified. Biallelic CRB1 mutations can cause anatomical fovea disruption similar to XLRS but have very different electroretinogram findings. This case report enhances our understanding of the spectrum of biallelic CRB1 mutations.

KEYWORDS:

• CRB1
• CRB1-associated maculopathy
• foveoschisis
• macular dystrophy

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The author(s) reported that there is no funding associated with the work featured in this article.