Prenatal exclusion of Norrie disease with flanking DNA markers

Abstract
Three polymorphic DNA markers linked to the locus of Norrie disease were used for indirect genotype analysis in a ten‐wk‐old fetus at risk for the disease. When haplotypes of the family members and the estimated recombination frequency between Norrie gene and each of the DNA marker loci DXS7, DXS84, and DXS146 were taken into account, the risk that the fetus had inherited the mutation was about 1%.