Glycine substitution mutations by different amino acids in the same codon of COL7A1 lead to heterogeneous clinical phenotypes of dominant dystrophic epidermolysis bullosa

Dystrophic epidermolysis bullosa (DEB), caused by mutations in the gene enc oding type VII collagen (COL7A1), is known to show heterogeneous clinical p henotypes. Certain correlations between the nature or position of COL7A1 mu tations and the resultant DEB phenotypes have been suggested, although such relationships may be more complex than initially thought, The purpose of t he present study was to clarify the molecular basis of two different subtyp es of dominant DEB (DDEB), EB pruriginosa and classical type, Interestingly , we found that both cases were caused by a missense glycine substitution m utation by different amino acids in the same codon of COL7A1 (G2028R and G2 028A), These results further support the notion that different glycine subs titution mutations in the same codon can lead to heterogeneous clinical phe notypes of DDEB, EB pruriginosa and classical type.