Congenital blindness: report of leber congenital amaurosis in a large Iranian Kindred

ABSTRACT

Leber congenital amaurosis [LCA] is a hereditary neonatal blindness. Congenital blindness is common among a specific branch of the Lore tribes in Kerman province, central Iran. This study was designed to identify all affected patients, construct a pedigree for obtaining the transmission pattern, establish definite diagnosis, and finally determine the genetic origin of the blindness among this tribe. Using several field studies, over a period of 2 years, and conducting interviews with senior members of the tribe, a total of 25 patients were identified. Electrophysiological tests and karyotyping were undertaken for appropriate cases. DNA samples collected from a group of affected individuals and their first-degree relatives were used to evaluate genetic linkage to a number of known loci on different chromosomes. Autosomal recessive pattern of inheritance and neonatal visual impairment without any noticeable eye lesions was documented. Infantile nystagmus, keratoconus, narrowing of retinal vessels, retinal degeneration, mild pigmentary retinopathy and electrophysiological investigations were consistent with LCA. Only one locus on 17p13.1 was consistent with linkage in this kindred. We made a large pedigree of LCA for the first time in Iran. Mutation screening of the responsible gene is currently in progress