Erratum: Analysis of Dosage Mutation in PARK2 among Korean Patients with Early-Onset or Familial Parkinson's Disease

Authors would like to change annotation of variants in Table 1 and its legend according to HGVS nomenclature recommendation.

Analysis of Dosage Mutation in PARK2 among Korean Patients with Early-Onset or Familial Parkinson's Disease

BACKGROUND AND PURPOSE: There is some controversy regarding heterozygous mutations of the gene encoding parkin (PARK2) as risk factors for Parkinson's disease (PD), and all previous studies have been performed in non-Asian populations. Dosage mutation of PARK2, rather than a point mutation or small insertion/deletion mutation, was reported to be a risk factor for familial PD; dosage mutation of PARK2 is common in Asian populations. METHODS: We performed a gene-dosage analysis of PARK2 using real-time polymerase chain reaction for 189 patients with early-onset PD or familial PD, and 191 control individuals. In the case of PD patients with heterozygous gene-dosage mutation, we performed a sequencing analysis to exclude compound heterozygous mutations. The association between heterozygous mutation of PARK2 and PD was tested. RESULTS: We identified 22 PD patients with PARK2 mutations (11.6%). Five patients (2.6%) had compound heterozygous mutations, and 13 patients (6.9%) had a heterozygous mutation. The phase could not be determined in one patient. Three small sequence variations were found in 30 mutated alleles (10.0%). Gene-dosage mutation accounted for 90% of all of the mutations found. The frequency of a heterozygous PARK2 gene-dosage mutation was higher in PD patients than in the controls. CONCLUSIONS: Heterozygous gene-dosage mutation of PARK2 is a genetic risk factor for patients with early-onset or familial PD in Koreans.

Significance of Thymidylate Synthase Expression in Colorectal Cancer

PURPOSE: Thymidylate synthase (TS) is the target enzyme for 5-fluorouracil (5-FU). It is known that TS is related to response, and resistance, following chemotherapy due to colorectal cancer. The object of this study was to identify the clinical significance of TS as a prognostic factor, and its influence on 5-FU based chemotherapy in colorectal cancer. METHODS: We performed a retrospective study on 105 consecutive patients who were operated on, at the Department of Surgery, Korea University, College of Medicine, for colorectal cancer between Jan. 1994 and Dec. 1995. We used formalin fixed, paraffin embedded tissues of resected specimens for our study. For the semi-quantitative study, the specific monoclonal antibody, TS106, was used for immunohistochemical staining. Interpretation of the immunohistochemical staining, for intratumoral TS expression, was divided into 4 grades: intensity 0, 1 , 2 , 3 were defined as, a total absence of TS immuno staining, less than 25%, 25~50% and more than 50%, of tumor staining positive, respectively. Grades 0, 1 , and 2 were regarded as low TS expression groups and 3 regarded as a high TS expression group. We then analyzed 5-year survival rates, according to Dukes' stage, and whether systemic chemotherapy was performed, or not, according to TS expression. RESULTS: Of the 105 patients, 91 (86.7%) showed TS expression, 21 (20%) with high TS expression and 84 (80%) were low TS expression. As Dukes' stage advanced, the incidence of high expression of TS increased (P=0.048). In Dukes' stage B2, 5-year survival rates for the low TS expressed group was better than for the high TS expressed group (P=0.0052). In patients who received postoperative chemotherapy, 5-year survival rates for the low TS expressed group were better than for the high TS expressed group (P=0.049). CONCLUSION: These data suggest the expression of intratumoral TS, studied by immunohistochemical staining, is relevant to the prognosis of colorectal cancer, especially Dukes' stage B2. It is also related to the response rate of 5-FU based systemic chemotherapy in colorectal cancer.

Association of Human Papillomavirus with Human Colorectal Cancer

PURPOSE: The aim of this study is to confirm the association of human papillomavirus with colorectal cancer. METHODS: We studied 44 patients who were received operation for colorectal cancer from 1, Jan. 1997 to 31, Dec. at Korea University Guro Hospital. We used paraffin- embedded tissue sections of colorectal adenocarcinomas and human cervical cell lines as a positive control. We also studied 10 cases of anal canal squamous cell carcinomas. The extracted DNA were analyzed by polymerase chain reaction and enzyme restriction method. RESULTS: Human papillomavirus DNA was not detected in all specimen of colorectal adenocarcinomas. But in 3 of 10 (30%) of anal canal squamous carcinomas, human papillomavirus DNA was detected. We identified this human papillomvirus DNA as type 16 by enzyme restriction technique. CONCLUSIONS: Human papillomavirus usually associated with malignant transformation are present in anal canal squamous cell carcinomas. This study also showed same result. But this association was absent from adenocarcinoma of the colon and rectum.