Phenotype-genotype Correlations In Patients With Wilson’s Disease

Aims: Our study is through collecting clinical data in patients with Wilson’s disease, and their blood samples were collected to test of ATP7 B gene. The result of genetic mutations with clinical phenotype characteristics were analyzed, aimed to explore the impact of genetic variation for the disease occurrence, development and prognosis.Methods: On the basis of understanding and signing the informed consent form, collected data of 68 cases of WD patients personal basic information, disease history, clinical manifestations, biochemical index, diagnosis and treatment of history, family history, and, also collected venous blood samples were sent to Shenzhen China clinical inspection center, using ngs(next generation sequencing) determination of specimens of ATP7 B gene DNA double strand, search the gene mutation.Results: 1. 66 out of the 68 WD patients(97.06%) harbored at least one mutation. Among the 48 different mutations, 35 were missense, one was nonsense, two were splicing, and 10 were frameshift(five insertion and five deletion). 2. The mutations were distributed in exon 1, 2, 5, 7, 8, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, and 20 and intron 4 and 13. Exon 8(6/48) was showed to more frequent to suffer the mutations, followed by exon 11(5/48), exon 18(5/48), exon 13(4/48), and exon 16(4/48) suggesting these exons might be more susceptible to Wilson disease in Chinese Han population. 3. Then the SNPs of the patients were analyzed, a total of eight SNPs were identified, both of which had been reported in the past. 4. After comparing with the previous reports and WD gene mutation database, 22 out of the 48 mutations were identified to be novel. 5. Arg778 Leu mutation group and no Arg778 Leu mutation groups were compared, the difference between the serum ceruloplasmin, ALT, ALP has statistical significance(P < 0.05) that Arg778 Leu mutation group had a lower level of serum ceruloplasmin protein, ALT, ALP, and although two groups for AST had no significant difference, but with no mutation group, Arg778 Leu mutation group AST values lower, suggesting the presence of Arg778 Leu mutation patients tend to have lower serum ceruloplasmin and mild liver injury. 6. Pro992 leu mutation group and no pro992 leu mutation groups were compared, the difference between the serum ceruloplasmin protein, AST, ALT, ALP is statistically significant, indicating that pro992 leu mutation group had a higher level of serum ceruloplasmin protein, AST, ALT, ALP, suggesting the presence of pro992 leu mutation affected tendency in the high level of serum ceruloplasmin and heavier liver injury. 7. The patients with c.2975C>T mutation or c.3809A>G mutation mostly presented WD features before 12 years old while the patients with c.3443T>C mutation almost presented WD features after 12 years old. On the other hand, the patients with c.2333G>T mutation, the prevalent mutations in Chinese WD patients, showed no little contribution on the onset age, among which, the patients frequency with onset age ≤12 years old was similar with that in total patients.Conclusion: 1. A total of 68 patients with WD were recruited into the study. Genetic testing was performed in all patients. In this study, the detection rate of gene mutation is 97.06%, and the mutation forms are diverse. We found 48 kinds of mutant forms, and among them,22 kinds were the new mutations. 2. Arg778 Leu mutation and pro992 leu mutation is the study of high frequency mutation region, and may be related to certain the patients serum ceruloplasmin and liver function enzymes. 3. At the same time, we analyze the onset age less than 12 years old patients with gene mutations. Patients with c.2975C>T mutation, c.3809A>G mutation tend to have a lesion before the age of 12, c.3443T>C mutations in the patient is inclined to after 12 year. But c.2333G>T mutation, the prevalent mutations in Chinese WD patients, shows no little contribution on the onset age. 4. However, the sample size of this study is small, and there are limitations in this stidy. It is still necessary to further expand the sample size and explore the relationship between genotype and clinical phenotype.