Abstract
Foveal hypoplasia is the major cause of visual loss. Here we report an isolated foveal hypoplasia patient without nystagmus. It is very rare, and its etiology is not completely understood. Using whole-exome sequencing and foveal hypoplasia-related gene filtering from a family with two generations, we identified a novel variant c.859T>C (p.S287P) and a rare non-frameshift variant c.229_230insGGG (p.Arg77_Glu78insGly) in the tyrosinase (TYR) gene that co-segregated in the affected member of this family. The compound heterozygous variants inherited in the proband were confirmed by Sanger sequencing and predicted from in silico studies to have an effect on protein function. In conclusion, our finding extends the spectrum of TYR variants and supports the important role of TYR in the development of eyes.
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Acknowledgements
We thank the family for their participation in our study. We also acknowledge Miao Zhu, for his sequencing data analysis support.
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This work was supported by the National Natural Science Foundation of China (Grant number 61871121).
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TX and QZ: manuscript writing and data collection. YL and YB: sequencing and data analysis. YB and WZ: manuscript writing and overall instruction. All authors read and approved the final manuscript.
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Xu, T., Zhou, Q., Li, Y. et al. Novel compound heterozygous variants of tyrosinase gene in an isolated foveal hypoplasia patient without nystagmus. J Hum Genet 66, 543–548 (2021). https://doi.org/10.1038/s10038-020-00872-z
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DOI: https://doi.org/10.1038/s10038-020-00872-z
