Swiss Family with Dominant Stargardt Disease Caused by a Recurrent Mutation in the ELOVL4 Gene

Background

Stargardt (STGD) disease is responsible for 7 % of all retinal dystrophies and affects 1 in 10 000 people [1]. The typical onset occurs during the first two decades of life, which makes it the most common form of juvenile macular degeneration. It rapidly progresses and has a poor visual prognosis. STGD has been associated with considerable clinical and genetic heterogeneity. STGD can be classified into three variants based on the gene affected and is transmitted as an autosomal recessive or dominant disorder. Nearly two thirds of the cases, classified as STGD1, are caused by mutations in the ATP-binding cassette transporter, retina specific gene (ABCA4 on chromosome 1p21–22) and have predominantly autosomal recessive inheritance. The other one third of the cases has been linked to two different variants, the STGD3 and STGD4. STGD3 (OMIM 600 110) is associated with mutations in the elongation of very long chain fatty acids-like 4 gene (ELOVL4) on chromosome 6q16 [2], [3], [4]. It has an autosomal dominant inheritance whereas STGD4 is associated to mutations in the prominin 1 gene (PROM1) on chromosome 4. Mutations in ELOVL4 are rare and only 9 variants have been described so far (6 single nucleotide and 3 indel/del mutations) [2], [3], [5], [6], [7], [8], [9]. But from these mutations, only 4 are associated with STGD3. The others were identified in patients with neuro-ichthyotic disorders or age-related maculopathy. The purpose of this report is to describe the clinical and genetic study of a 2-generation family with dominant Stargardt disease due to ELOVL4 mutation.

^* Both authors contributed equally to this work.

• References

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