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Hepatic Wilson's disease is often a difficult diagnosis to confirm. This review examines the current role of genetic tests for Wilson's disease and is aimed at clinicians caring for patients with this disease. We discuss how genetic testing is carried out for Wilson's disease, indications for these tests, and genetic counseling for the family. In contrast to the advances in diagnosis of Wilson's disease by testing for ATP7B mutations, genotype-phenotype correlations are not yet sufficiently established. The non-Wilsonian copper overload syndromes causing cirrhosis in children are another important area for study. The review also identifies further areas for research into the genetics of Wilson's disease in India.

Background: Wilson's disease (WD) is an autosomal recessive disorder leading to copper overload, mainly in the liver and brain, due to mutations in the ATP7B gene. About 10% of heterozygous carriers of ATP7B gene mutations have decreased serum ceruloplasmin, posing diagnostic difficulties., Case Report: We report a four-member family wherein the 11-year-old daughter was diagnosed as having WD based on standard biochemical tests and the presence of Kayser Fleischer rings. On screening the entire family for WD, both parents and her eight-year-old brother had no clinical evidence of WD. However, serum ceruloplasmin was markedly decreased in the brother and was borderline low in the father, raising the possibility that the brother also had WD. We used conformation-sensitive gel electrophoresis (CSGE) to screen for mutations in the ATP7B gene in this family. Using CSGE we found that the patient's father and brother had an aberrant pattern in exon 8 of the ATP7B gene, the mother an aberrant pattern in exon 13, while the daughter (the index patient) had aberrant patterns in exons 8 and 13 of the ATP7B gene. DNA sequencing revealed that the index patient was a compound heterozygote with 2292-2312de121bp (a novel mutation) and Arg969Gln mutations, while the father and brother were heterozygous for the 2292-2312de121bp mutation and the mother for the Arg969Gln mutation., Conclusions: This case report illustrates the utility of CSGE in analyzing mutations in the ATP7B gene to resolve diagnostic dilemmas arising in heterozygous carriers with low serum ceruloplamin.

Objective: To analyze ATP7B mutations in Wilson's disease (WD) patients from the Indian subcontinent and to correlate these with WD phenotype., Methods: We studied 27 WD patients from 25 unrelated families. Twenty-two families were from three southern Indian states - Tamil Nadu andhra Pradesh and Kerala. We applied conformation- sensitive gel electrophoresis (CSGE) to screen for the mutations in patients and their families. PCR products exhibiting aberrant patterns in CSGE were subjected to direct DNA sequencing. As siblings affected by WD within a family share identical ATP7B genotype, we compared WD phenotype among affected siblings within families., Results: ATP7B mutations were detected in 22 of the 25 probands -13 were homozygotes and 9 were compound heterozygotes. Eleven novel mutations were detected. Only two common mutations were found: G3182A in 4 (16%) and C813A in 3 (12%) probands. 'Hot spots' for ATP7B mutations were exons 18 and 13. Lack of common dominant mutations prevented correlation of individual ATP7B mutations with WD phenotype. Symptomatic WD in a live sibling was not found in any family. In 8 families, a sibling died of presumed WD - in 6 of these, WD phenotype was identical to that in the proband., Conclusions: We describe the spectrum of ATP7B mutations including 11 novel mutations in Indian WD patients and document lack of a single dominant mutation. Identical WD phenotype among siblings in only 6 of 8 families with >1 child affected by WD suggests that factors other than ATP7B mutations influence WD phenotype.