Suggested problems

Synonymous SNPs

Oct. 15, 2012, 9:30 a.m. by Dennis Farr

Biological Motivation

When several codons code for the same amino acid, the codon may influence the folding of the protein at that point, and the mechanism for this is not fully explained. (It is possible that the choice of stop codon also influences folding.)

A single nucleotide polymorphism (SNP) is one of the simplest possible mutations (along with additions and deletions). A synonymous SNP in a coding region of DNA results in the identical amino acid sequence in the resulting protein. ...


When multiple codons code for an amino acid, the codon choice may influence protein folding at the amino acid. A large number of DNA strings result in the same amino acid string.

Given: A protein string of length at most 20 amino acids.

Return: The number of different DNA strings encoding the protein.

Sample Dataset


Sample Output