Novel TYR mutations and resulting OCA1 phenotypes. A. Electropherograms of amplimers from genomic DNA templates illustrating homozygosity for the substitution mutations found in the affected individuals of the families. Arrows indicate the site of the mutations. All of the mutations described here are numbered from the ATG start codon (GenBank NM_000372). B. Clustal W alignment of tyrosinase proteins from various species that shows the conservation of residues at positions 21, 35 and 411 among ten species. The conserved amino acids are shown with a dark gray background, and the nonconserved amino acids are shown with a white background. C. Photographs of ten OCA1 probands. The family number and the mutation identified in the TYR gene are given for each proband; some of the probands have used hair dyes.