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Mutations in PARK2 are considered a common cause of Parkinson’s disease (PD). To assess the frequency of PARK2 mutations in the Korean population, we screened the PARK2 gene in 83 Korean PD patients: two young onset (YO, ≤ 49), 32 middle onset (MO, 50–69) and 49 late onset (LO, ≥ 70). Detection of the point mutations was performed by direct sequencing of the PARK2 exons, and exonic rearrangements were analyzed using multiplex ligation-dependent probe amplification. Five known PARK2 variants were identified in 53 (63.9 %) of the Korean PD patients: two missense mutations (Y267H and M458L) and three polymorphisms (S167N, L272I and V380L). We also found an increased frequency of PARK2 variants in PD patients and a lowered PD age at onset (AAO) in those having two variants, suggesting that the genetic variation in PARK2 gene might be a genetic risk factor of PD in Korean population.

Background Detection of antibodies to extractable nuclear antigens (ENAs) and dsDNA is needed for the diagnosis of and predicting prognosis in systemic autoimmune diseases. Recently introduced line immunoassay (LIA) has the advantage of detecting several autoantibodies simultaneously, and we evaluated its usefulness in the diagnosis of autoimmune diseases in comparison with enzyme-linked immunosorbent assay (ELISA). Methods Samples were collected from 437 patients referred by rheumatologists. FANA (fluorescent antinuclear antibody) test and LIA for the detection of 13 different autoantibodies, including 6 ENAs and dsDNA were performed. LIA-positive samples for ENA or dsDNA antibodies were further tested with ELISA. Final diagnosis was made by rheumatologists according to the diagnostic criteria. Agreement of results between LIA and ELISA was analyzed in 53 selected patients with systemic autoimmune diseases. Results The LIA detected antibodies to ENA and dsDNA in 118 and 22 patients, respectively, and ELISA detected 70.3% (83/118) and 45.5% (10/22) of LIA positive samples. Especially, 60.2% (71/118) of patients with positive ENA antibody on LIA was diagnosed as systemic autoimmune diseases. Patients having strong FANA titer and homogenous/speckled pattern showed higher prevalence of autoantibodies, but a small proportion of FANA negative patients also showed positive reactivity (LIA 10.8%, ELISA 5.2%). LIA showed a good agreement with ELISA for the anti-ENA antibodies (> or =80%), and a lower agreement for the anti-dsDNA antibody (67.9%). Conclusions LIA detecting several autoantibodies simultaneously might replace ELISA for anti-ENA antibodies, but not for anti-dsDNA antibodies. When LIA is performed considering clinical manifestations and FANA, it could contribute to the diagnosis of systemic autoimmune disease.

A series of 20 hepatocellular carcinomas and 8 intrahepatic cholangiocarcinomas was screened from the Korean population for microsatellite alterations, including a loss of heterozygosity and replication errors using nine microsatellite markers containing several genes. The microsatellite results and our previous comparative genomic hybridization results of two tumors were compared at each locus, and the correlations between these and clinicopathologic variables were examined. The most characteristic findings were found at 13q. Replication errors were prevalent at D13S160 (13q21.2 approximately q31) and D13S292(13q12). The incidence of loss of heterozygosity, however, was higher at D13S153 (13q14.1 approximately q14.3) and D13S265(13q31 approximately q32). In contrast, there were higher deletion frequencies observed in hepatocellular carcinoma (HCC) and higher amplification frequencies observed in intrahepatic cholangiocarcinoma at 13q in our previous comparative genomic hybridization (CGH) study. Higher frequencies of replication errors were observed at D16S408 (13q12 approximately q21) and D16S504(13q23 approximately q24) in the HCC. This study found that significant differences in the patterns of genetic instability of microsatellites were dependent on the chromosomal loci. It is believed that certain genes at altered CGH regions, which are relevant to the development and/or progression of these cancers, are activated by different mutation mechanisms.

In the following study, we used comparative genomic hybridization (CGH) to screen and compare for genetic alterations of hepatocellular carcinoma (HCC) and intrahepatic choalgiocarcinoma (ICC). The studies showed distinctive features of genetic alterations between the two tumors. Characteristic abnormal changes for HCC were 1q gain and loss of 4q, 10q and 13q regions. In contrast, gains of 5p, 7p, 13q and 20q were more predominant in ICC. Losses of 16q, 17p, and 18q, and gain of 8q region showed a similar high frequency of incidence in both tumors. The most striking and different findings were 1q amplification in HCC and 20q gain in ICC. Our data indicate that ICC shows the pattern of genetic alterations similar to pancreatic and colorectal cancers. This suggests that the genetic alterations in tumorigenesis show a similar pattern depending on the origin of cells, not the organ.

Embryonic stem (ES) cells are a useful system to study cardiac differentiation in vitro. It has been difficult, however, to track the fates of chamber-specific cardiac lineages, since differentiation is induced within the embryoid body. We have established an in vitro culture system to track Nkx2.5(+) cell lineages during mouse ES cell differentiation by using green fluorescent protein (GFP) as a reporter. Nkx2.5/GFP(+) cardiomyocytes purified from embryoid bodies express sarcomeric tropomyosin and myosin heavy chain and heterogeneously express cardiac troponin I (cTnI), myosin light chain 2v (MLC2v) and atrial natriuretic peptide (ANP). After 4-week culture, GFP(+) cells exhibited electrophysiological characteristics specific to sinoatrial (SA) node, atrial, or ventricular type. Furthermore, we found that administration of 10(-7) M retinoic acid (RA) to embryoid bodies increased the percentage of MLC2v(-)ANP(+) cells; this also increased the expression of atrial-specific genes in the Nkx2.5/GFP(+) fraction, in a time- and dose-dependent fashion. These results suggest that Nkx2.5(+) lineage cells possess the potential to differentiate into various cardiomyocyte cell types and that RA can modify the differentiation potential of Nkx2.5(+) cardiomyocytes at an early stage.

Structural variations of DNA greater than 1 kilobase in size account for most bases that vary among human genomes, but are still relatively under-ascertained. Here we use tiling oligonucleotide microarrays, comprising 42 million probes, to generate a comprehensive map of 11,700 copy number variations (CNVs) greater than 443 base pairs, of which most (8,599) have been validated independently. For 4,978 of these CNVs, we generated reference genotypes from 450 individuals of European, African or East Asian ancestry. The predominant mutational mechanisms differ among CNV size classes. Retrotransposition has duplicated and inserted some coding and non-coding DNA segments randomly around the genome. Furthermore, by correlation with known trait-associated single nucleotide polymorphisms (SNPs), we identified 30 loci with CNVs that are candidates for influencing disease susceptibility. Despite this, having assessed the completeness of our map and the patterns of linkage disequilibrium between CNVs and SNPs, we conclude that, for complex traits, the heritability void left by genome-wide association studies will not be accounted for by common CNVs.

Screening of high-risk patients using bladder tumor markers can offer an advantage of early detection and saving medical costs. For these purpose many tumor markers have been developed to supplement invasive cystoscopy. Our study evaluated the NMP22 point-of-care test (NMP22 POCT), which is one of the tumor makers, comparing with the standard urine cytology for the diagnosis of bladder cancer.From January to September 2005, 232 patients who had undergone a cystoscopy due to bladder cancer associated symptoms including hematuria and dysuria were enrolled in this study. Urine specimens were collected for NMP22 POCT and cytology. NMP22 POCT and urine cytology were compared for sensitivity and specificity. In addition, we evaluated urine stick test and microscopy to explain some false-positive results in NMP22 POCT.Superficial transitional cell carcinoma was diagnosed in 10 patients. The sensitivity of NMP22 test was 60% (95% confidence interval [CI], 26.2-87.8%), whereas that of cytology was 33.3% (95% CI, 7.5-70.1%); however, the difference was not significant. The specificity of NMP22 test was 69.8% (95% CI, 63.3-75.8%), compared with 99.0% (95% CI, 96.5-99.9%) for cytology (P0.001). The presence of microscopic RBCs in urine specimen was significantly associated with the lower specificity of NMP22 POCT (P=0.02).NMP22 POCT was significantly less specific than urine cytology. To be useful as a bladder cancer screening test, the NMP22 test should have a higher specificity.

The World Health Organization declared that a new strain of novel swine-origin influenza A (H1N1) virus was responsible for the pandemic infection in June 2009. We report a case of encephalitis diagnosed as the H1N1 virus infection. We describe a 17-year-old patient who had a seizure attack, diagnosed with a H1N1 virus infection via real time reverse-transcriptase polymerase chain reaction (RT-PCR). The H1N1 virus infection can be causative of the encephalitis, as with other influenza virus infections. Careful monitoring is essential for reducing complications.

Comparative genomic hybridization (CGH) and conventional cytogenetic karyotyping were used to screen for losses and gains of DNA sequences along all chromosome arms in 16 bladder tumors. Cytogenetic results were highly complex. The most frequently affected chromosomes were 5, 8, 9, 21, and Y as determined by karyotyping. There was close correlation between the CGH data and cytogenetic results in near-diploid tumors with simple karyotypes. However, some unexpected results were observed by CGH in tumors with several composite clones. Common amplification of copy numbers of DNA sequences by CGH were seen at 1q, 3q, 4q, 5p, 6p/q, 7p, 8q, 11q, 12q, 13q, 17q, 18q, and 20p/q (more than 20% of cases). High level amplification was noted at 1p32, 3p21, 3q24, 4q26, 8q21-qter, 11q14-22, 12q15-21, 12q21-24, 13q21-31, 17q22, and 18q22. Deletions were noted at 2q21-qter. 4q13-23, 5q, 8p12-22, 9p/q, and 11p13-15 (more than 20% of cases). Although most amplifications and deletions have been previously described in the literature, our study showed some intriguing and uncommon regions, different from those found in past studies. These were the amplification of 7p, 8q, 11q14-qter 12q24-24, 13q21-31, and 18q22, and deletion on 4q13-23, even though loss of heterozygosity was not detected at this locus. In spite of the very complex pattern of genetic changes in bladder tumors, most of these uncommon aberrations have to be implicated in bladder tumors, and further molecular genetic methods are necessary to establish whether the chromosomal regions contain candidate genes which contributed to the initiation and progression of bladder tumors.