Figure 4: Sanger sequencing of MAFB gene. (a) Proband forward demonstrating a heterozygous missense mutation at nucleotide 197 from C to G (c.197C>G) that predicts the change of amino acid at codon 66 from serine to cysteine (p.Ser66Cys). The sequences of the unaffected mother (b) and the father (c) showing normal nucleotides TCC at codon 66.