Results
The authors identified three heterozygous mutations in four unrelated patients, of which two mutations were previously described and one was a novel missense mutation (Table 1). All identified mutations were heterozygous suggesting that these patients had compound heterozygous mutations. There were G to T at the nucleotide position
2333 (G2333T, Arg788Leu), C insertion at the position 2299 (2299insC) and a novel C to G at the nucleotide position 2297 (C2297G, Thr766Arg) (Fig. 1a). The new Thr766Arg was identified in a 22-year-old patient who developed Parkinsonism, marked postural tremor and Kayser-Fleischer ring for 6 months. It was absent in 100 normal control samples. Amino acid position 766 is in a transmembrane domain 4 (Tm4) of the ATP7B. Sequence of amino acids of the Tm4 was compared to transmembrane domain of ATP7 protein of other species showing that it is very highly conserved between different species (Fig. 1c).