To the Editor.
—In the article by Khouri et al1 in the October 1988 issue of the Archives, the authors state, "We report on a family in which three of the five affected members had hyperopia and could be classified as the incomplete type and in which a fourth member with myopia was more consistent with the complete type."Recent evidence has shown that congenital stationary night blindness of the complete type (CSNB1) and congenital stationary night blindness of the incomplete type (CSNB2)2,3 may be caused by two different genes on the X chromosome.4-7 Since no other authors have found both CSNB1 and CSNB2 in the families they studied,5,8,9 we would like to pose the following question: Can the authors provide a description of the electroretinogram testing conditions of all the patients tested, since we presume that IV-2 could be suffering from CSNB2. Weleber et al
Wright AF, VAN Dorp DB. X-Linked Congenital Stationary Night Blindness: Review and Report of a Family With Hyperopia. Arch Ophthalmol. 1991;109(6):766. doi:10.1001/archopht.1991.01080060020005