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. 2021 Mar;23(3):479-487.
doi: 10.1038/s41436-020-00997-8. Epub 2020 Oct 26.

Dopachrome tautomerase variants in patients with oculocutaneous albinism

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Free article

Dopachrome tautomerase variants in patients with oculocutaneous albinism

Perrine Pennamen et al. Genet Med. 2021 Mar.
Free article

Abstract

Purpose: Albinism is a clinically and genetically heterogeneous condition. Despite analysis of the 20 known genes, ~30% patients remain unsolved. We aimed to identify new genes involved in albinism.

Methods: We sequenced a panel of genes with known or predicted involvement in melanogenesis in 230 unsolved albinism patients.

Results: We identified variants in the Dopachrome tautomerase (DCT) gene in two patients. One was compound heterozygous for a 14-bp deletion in exon 9 and c.118T>A p.(Cys40Ser). The second was homozygous for c.183C>G p.(Cys61Trp). Both patients had mild hair and skin hypopigmentation, and classical ocular features. CRISPR-Cas9 was used in C57BL/6J mice to create mutations identical to the missense variants carried by the patients, along with one loss-of-function indel. When bred to homozygosity the three mutations revealed hypopigmentation of the coat, milder for Cys40Ser compared with Cys61Trp or the frameshift mutation. Histological analysis identified significant hypopigmentation of the retinal pigmented epithelium (RPE) indicating that defective RPE melanogenesis could be associated with eye and vision defects. DCT loss of function in zebrafish embryos elicited hypopigmentation both in melanophores and RPE cells.

Conclusion: DCT is the gene for a new type of oculocutaneous albinism that we propose to name OCA8.

Keywords: DCT; albinism; mouse; pigmentation; zebrafish..

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References

    1. Grønskov K, Ek J, Brondum-Nielsen K. Oculocutaneous albinism. Orphanet J Rare Dis. 2007;2:43–51. - DOI
    1. Montoliu L, Grønskov K, Wei AH, et al. Increasing the complexity: new genes and new types of albinism. Pigment Cell Melanoma Res. 2014;27:11–18. - DOI
    1. Kruijt CC, de Wit GC, Bergen AA, Florijn RJ, Schalij-Delfos NE, van Genderen MM. The phenotypic spectrum of albinism. Ophthalmology. 2018;125:1953–1960. - DOI
    1. Poulter JA, Al-Araimi M, Conte I, et al. Recessive mutations in SLC38a8 cause foveal hypoplasia and optic nerve misrouting without albinism. Am J Hum Genet. 2013;93:1143–1150. - DOI
    1. Lasseaux E, Plaisant C, Michaud V, et al. Molecular characterization of a series of 990 index patients with albinism. Pigment Cell Melanoma Res. 2018;31:466–474. - DOI

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