Figure 3. Partial nucleotide sequence of exon 12 of TGFBI in affected and unaffected individuals. A: A normal sequence is shown where the isoleucine is encoded by codon 522. B and C: The forward and reverse sequence shows a heterozygous genotype (1565T→A) in all the affected family members, which resulted from a change of isoleucine (ATC) to asparagine (AAC) at codon 522, thus altering the structure and property of the protein.