PROVEAN predicts the impact of small indels on protein function.

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In addition to single amino acid substitutions, there are other variation classes associated with disease phenotypes. For example, a common disease variant associated with the genetic disease cystic fibrosis is a deletion of phenylalanine at position 508, part of the ATP-binding domain of the CFTR protein. The prevalence of the ΔF508 allele in cystic fibrosis patients was 71% [14], [15]. In the Human Gene Mutation Database (Professional ver2011.3), at the gene sequence level approximately half of the human disease variations are associated with single nucleotide substitutions (57%), and close to one-fourth of disease mutations (22%) are associated with small indels [16], [17].