title: Phenotypic Variation in a Family With Pseudodominant Stargardt Disease.
abstract: OBJECTIVE
  Stargardt disease is a phenotypically diverse macular dystrophy caused by the autosomal recessive inheritance of mutations in ABCA4. Pseudodominant transmission occurs more often than might be expected because of the relatively high carrier frequency of pathogenic ABCA4 variants. Genetic characterization of affected individuals permits a more precise understanding of these genotype-phenotype associations.
  
  
  METHODS
  In this case series, we explore the clinical courses and genotypes of a woman and her 2 daughters with pseudodominant transmission of Stargardt disease. The mother had choroidal neovascularization that was treated with bevacizumab. Both daughters exhibited worse vision than their mother, despite lacking choroidal neovascularization, because of the extent of photoreceptor and retinal pigment epithelium atrophy in the macula. Genetic testing confirmed pseudodominant inheritance and the presence of 3 ABCA4 alleles within the family.
  
  
  CONCLUSIONS
  These cases emphasize the clinical relevance of recognizing pseudodominant transmission and the resultant phenotypic variability. Differing degrees of visual impairment in these patients emphasize the need to continue refining our understanding of how individual ABCA4 mutations contribute to phenotype.
authors.affiliation: Stephen A. Wynn Institute for Vision Research, Iowa City, Iowa2Department of Ophthalmology and Visual Sciences, University of Iowa Carver College of Medicine, Iowa City.
authors.forename: Rachel M
authors.initials: RM
authors.lastname: Huckfeldt
authors.affiliation: Stephen A. Wynn Institute for Vision Research, Iowa City, Iowa2Department of Ophthalmology and Visual Sciences, University of Iowa Carver College of Medicine, Iowa City.
authors.forename: Jade S
authors.initials: JS
authors.lastname: East
authors.affiliation: Stephen A. Wynn Institute for Vision Research, Iowa City, Iowa3Howard Hughes Medical Institute, Iowa City, Iowa.
authors.forename: Edwin M
authors.initials: EM
authors.lastname: Stone
authors.affiliation: Stephen A. Wynn Institute for Vision Research, Iowa City, Iowa2Department of Ophthalmology and Visual Sciences, University of Iowa Carver College of Medicine, Iowa City.
authors.forename: Elliott H
authors.initials: EH
authors.lastname: Sohn