Published online Sep 28, 2017. doi: 10.3748/wjg.v23.i36.6715
Peer-review started: May 5, 2017
First decision: June 7, 2017
Revised: June 16, 2017
Accepted: July 12, 2017
Article in press: July 12, 2017
Published online: September 28, 2017
Processing time: 144 Days and 7.6 Hours
To determine the phenotypes and predominant disease-causing mutations in Lebanese patients with Wilson’s disease, as compared to regional non-European data.
The clinical profile of 36 patients diagnosed in Lebanon was studied and their mutations were determined by molecular testing. All patients underwent full physical exam, including ophthalmologic slit-lamp examination ultrasound imaging of the liver, as well as measurement of serum ceruloplasmin and 24-h urinary-Cu levels. In addition, genetic screening using PCR followed by sequencing to determine disease-causing mutations and polymorphisms in the ATP7B gene was carried on extracted DNA from patients and immediate family members. Our phenotypic-genotypic findings were then compared to reported mutations in Wilson’s disease patients from regional Arab and non-European countries.
Patients belonged to extended consanguineous families. The majority were homozygous for the disease-causing mutation, with no predominant mutation identified. The most common mutation, detected in 4 out of 13 families, involved the ATP hinge region and was present in patients from Lebanon, Egypt, Iran and Turkey. Otherwise, mutations in Lebanese patients and those of the region were scattered over 17 exons of ATP7B. While the homozygous exon 12 mutation Trp939Cys was only detected in patients from Lebanon but none from the regional countries, the worldwide common mutation H1069Q was not present in the Lebanese and was rare in the region. Pure hepatic phenotype was predominant in patients from both Lebanon and the region (25%-65%). Furthermore, the majority of patients, including those who were asymptomatic, had evidence of some hepatic dysfunction. Pure neurologic phenotype was rare.
Findings do not support presence of a founder effect. Clinical and genetic screening is recommended for family members with index patients and unexplained hepatic dysfunction.
Core tip: We report on the genotype-phenotype of 36 Lebanese patients with Wilson’s disease from 13 different families. The majority were homozygous for disease-causing mutations. The most common mutation worldwide, His1069Trp, was absent in our patients. The ATP hinge region may comprise a hot spot for mutations, as it was detected in 4 families. Hepatic phenotypes were predominant in both symptomatic and asymptomatic patients. Neurologic phenotypes were rare. Compared to findings reported in regional Arab and non-European countries, our results do not support a founder effect. Mutations are scattered over 17 exons, with no common or frequent mutation characterizing the region.