Can Genome-Wide Profiling Discover Polymorphisms That Influence Cancer Risk?
Possibly. Studies of polymorphisms in individual patients and in populations are yielding interesting hints. Some (but not all) sequence polymorphisms appear to influence cancer risk. Some sequence polymorphisms may not themselves be associated with cancer risk but may serve as “markers” for nearby genes that do exert an influence. Polymorphisms within protein coding regions may alter the function of the encoded protein, particularly if they change its structure or amino acid sequence. Polymorphisms in regions of the DNA that regulate gene expression may result in altered protein levels, alternative splicing, or other modifications. Changes in a protein’s sequence or its regulation can influence cancer risk by altering how a person responds to carcinogens, drugs, chemicals, or other environmental exposures.
