Autosomal dominant osteogenesis imperfecta is caused by mutations in the COL1A2 
and COL1A1 genes of type I collagen. In a family with OI type IV genetically 
linked to the COL1A2 gene, we attempted prenatal diagnosis in a pregnancy at 
risk by genotyping the DNA of the fetus for a COL1A2 gene associated RFLP. Our 
results showed that the fetus inherited the normal COL1A2 allele from her 
affected parent. Linkage analysis can thus be used in the prenatal diagnosis of 
dominantly inherited osteogenesis imperfecta.