Stargardt disease caused by a rare combination of double homozygous mutations.

Stargardt disease is a juvenile macular degeneration most often inherited in an autosomal recessive pattern, characterized by decreased vision in the first 2 decades of life. This report presents a clinical case of Stargardt disease: a 10-year-old female patient complained of blurry vision, and in a 4-year period, her visual acuity was reduced from OD=0.3 and OS=0.3 to OD=0.08 and OS=0.1, respectively. A genetic analysis revealed a rare combination of 2 homozygous recessive mutations in the ABCA4 gene, which caused Stargardt disease. The presence of different genetic mechanisms leading to a severe disease phenotype can challenge molecular geneticists, ophthalmologists, and genetic counselors.