From family studies, we know that BCD is inherited primarily in an autosomal recessive fashion. This means that an affected person receives one nonworking gene from each of his or her parents. A person who inherits a nonworking gene from only one parent will be a carrier, but will not develop the disease. A person with BCD syndrome will pass on one gene to each of his or her children. However, unless the person has children with another carrier of BCD genes, the individual’s children are not at risk for developing the disease. More about autosomal recessive inheritance.

In September 2000, NEI researchers reported that the BCD gene had been localized to chromosome #4. In this region of chromosome #4 there are hundreds of genes. Researchers are now looking for which of the genes in this region of chromosome #4 causes BCD. Finding the gene may shed light on the composition of the crystals found in the corneas of patients with BCD and on what causes the condition. More about finding disease genes.