Cassette mutagenesis experiments suggest that the probability of attaining (at random) the correct sequencing for a short protein 100 amino acids long is about 1 in 10 to the 65 power(Reidhaar-Olson & Sauer 1990)
Recent mutagenesis research has provided additional support for the conclusion that functional proteins are exceedingly rare among possible amino acid sequences. The probability of finding a functional protein among the possible amino acid sequences corresponding to a 150-residue protein is similarly 1 in 10 to the 77 power.(Axe 2004)
It is unlikely that a new protein fold via a series of folded intermediates sequences (Blanco et al. 1999)
post-translation processes of modification in producing a functional protein make it impossible to predict a protein's final sequencing from its corresponding gene sequence alone (Sarkar 1996)
Muller, G. B. & S. A. Newman. 2003. Origination of organismal form: the forgotten cause in evolutionary theory. G. B. Muller and S. A. Newman, eds., Origination of organismal form: beyond the gene in developmental and evolutionary biology. M.I.T.
Thomson, K. S. 1992. Macroevolution: The morphological problem
Miklos, G. L. G. 1993. Emergence of organizational complexities during metazoan evolution: perspectives from molecular biology, palaeontology and neo-Darwinism.
Webster & Goodwin 1996; Shubin & Marshall 2000; Erwin 2000; Conway Morris 2000, 2003b; Carroll 2000; Wagner 2001; Becker & Lonnig 2001; Stadler et al. 2001; Lonnig & Saedler 2002; Wagner & Stadler 2003; Valentine 2004)