Genetic Factors Modifying Clinical Expression of Autosomal Dominant RP

Factors modifying clinical expression of inherited diseases are likely to be complex, involving genetic factors, environmental factors and stochastic effects. One way to reduce the complexity is to focus on individuals who share a dominant mutation identical by descent, thus eliminating variability in the underlying mutation and variation in cis to the mutation. A further simplification is to limit analysis to a single, extended family, which may reduce, though not eliminate, environmental effects.