Taking advantage of the enormous number of recombinants that could be analyzed in the rII mutant system, Benzer was eventually able to map over 2400 rII mutations. The data he collected provided the first evidence that the gene is not an indivisible entity, as previously believed, and that genes were linear. Based on his rII data, Benzer also proposed distinct classes of mutations including deletions, point mutations, missense mutations, and nonsense mutations.