Clinical Implications of Microsatellite Instability in Early Gastric Cancer

PURPOSE: We aimed to evaluate the clinical characteristics of microsatellite instability in early gastric cancer.MATERIALS AND METHODS: The microsatellite instability status of resected early gastric tumors was evaluated using two mononucleotide repeat markers (BAT25 and BAT26) and three dinucleotide repeat markers (D5S346, D2S123, and D17S250). Tumors with instability in two or more markers were defined as microsatellite instability-high (MSI-H) and others were classified as microsatellite stable (MSS).RESULTS: Overall, 1,156 tumors were included in the analysis, with 85 (7.4%) classified as MSI-H compared with MSS tumors. For MSI-H tumors, there was a significant correlation with the female sex, older age, tumor location in the lower gastric body, intestinal histology, lymphovascular invasion (LVI), and submucosal invasion (P<0.05). There was also a trend toward an association with lymph node (LN) metastasis (P=0.056). In mucosal gastric cancer, there was no significant difference in MSI status in tumors with LN metastasis or tumors with LVI. In submucosal gastric cancer, LVI was more frequently observed in MSI-H than in MSS tumors (38.9% vs. 25.0%, P=0.027), but there was no difference in the presence of LN metastases. The prognosis of MSI-H tumors was similar to that of MSS tumors (log-rank test, P=0.797, the hazard ratio for MSI-H was adjusted by age, sex, pT stage, and the number of metastatic LNs, 0.932; 95% confidence interval, 0.423–2.054; P=0.861).CONCLUSIONS: MSI status was not useful in predicting prognosis in early gastric cancer. However, the frequent presence of LVI in early MSI-H gastric cancer may help guide the appropriate treatment for patients, such as endoscopic treatment or limited LN surgical dissection.

HMOX1 Gene Promoter Polymorphism is Not Associated with Coronary Artery Disease in Koreans

BACKGROUND: The heme oxygenase-1 gene (HMOX1) promoter polymorphisms modulate its transcription in response to oxidative stress. This study screened for HMOX1 polymorphisms and investigated the association between HMOX1 polymorphisms and coronary artery disease (CAD) in the Korean population. METHODS: The study population consisted of patients with CAD with obstructive lesions (n=110), CAD with minimal or no lesions (n=40), and controls (n=107). Thirty-nine patients with CAD with obstructive lesions underwent follow-up coronary angiography after six months for the presence of restenosis. The 5'-flanking region containing (GT)n repeats of the HMOX1 gene was analyzed by PCR. RESULTS: The numbers of (GT)n repeats in the HMOX1 promoter showed a bimodal distribution. The alleles were divided into two subclasses, S25 and L25, depending on whether there were less than or equal to and more than 25 (GT)n repeats, respectively. The allele and genotype frequencies among groups were statistically not different. More subjects in the S25-carrier group had the low risk levels of high sensitivity C-reactive protein (hsCRP) for the CAD than those in the non-S25 carrier group (P=0.034). Multivariate logistic regression analysis revealed that the genotypes of (GT)n repeats were not related to CAD status. The restenosis group in the coronary angiography follow-up did not show any significant difference in HMOX1 genotype frequency. CONCLUSIONS: The HMOX1 genotypes were not found to be associated with CAD, but the short allele carrier group contained more individuals with hsCRP values reflecting low risk of cardiovascular disease in the Korean population.

EST-SSR identification of Lonicera japonica Thunb / 药学学报

Simple and effective methods are needed for the identification of Chinese medicinal material species and their variety. Lonicera japonica Thunb. is one of Chinese herbal medicines widely demanded. A total of 3 705 EST-SSRs of L. japonica and 2 818 EST-SSRs of L. japonica var. chinensis Thunb. were identified from EST database in our lab. In average, there was one EST-SSR per 4.05 kb in L. japonica ESTs and per 7.49 kb in L. japonica var. chinensis ESTs, separately. The identified SSRs in L. japonica were consisted of 51.98% dinucleotide and 34.61% trinucleotide repeats, while SSRs in L. japonica var. chinensis had 57.45% dinucleotide and 30.09% trinucleotide. The results reviewed that the classes AG/TC and GAG/TCT were predominant in the dinucleotide motifs and the trinucleotide motifs, respectively. Total 87 EST-SSRs were identified of significant difference between L. japonica and L. japonica var. chinensis. PCR products were obtained from 52 L. japonica samples in 13 out of 15 SSR markers tested. The polymorphism in L. japonica, L. japonica var. chinensis and other honeysuckles could be distinguished by three markers (jp.ssr4, jp.ssr64 and jp.ssr65) tested.

Association of polymorphisms of STAT6 and SO(2) with Chinese childhood asthma: a case-control study / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To investigate the association of polymorphisms of STAT6 gene and air pollutants of PM(10), NO(2), and SO(2), with asthma in Chinese children.</p><p><b>METHODS</b>418 subjects aged 14 years and under were recruited in a case-control study. The association between STAT6 polymorphisms and childhood asthma were tested by allele frequency, genotype analysis, and MDR analysis. Exposure to outdoor air pollutants was estimated by a 5-day moving average level. Statistical analyses were performed with SAS 9.1 software.</p><p><b>RESULTS</b>Only 3 alleles of GT repeats at exon 1 of STAT6 were found in Chinese children. C258T and T710C were 2 new SNPs of STAT6 at 3'-UTR. Children who carried T allele of C258T were more common in asthma children than in control subjects (P<0.05). The MDR analysis showed that GT repeats, C258T and T710C of STAT6 polymorphisms interacted together in leading to susceptibility to childhood asthma among Chinese people. After confounding factors were controlled, such as SNP C258T, family history of asthma, frequency of influenza within a year, the 5-day average of SO(2) was tested to be a key risk factor of asthma in Chinese children (P<0.05).</p><p><b>CONCLUSION</b>Chinese children differed in polymorphisms of STAT6 and in its relation with childhood asthma.</p>

Carrier detection and prenatal diagnosis of hemophilia A in a Korean population by fluorescent pcr analysis of dinucleotide repeats in intron 13 and intron 22 of the factor VIII gene / 대한산부인과학회지

OBJECTIVE: To set up the methodology for fluorescent PCR analysis of intron 13 and intron 22 microsatellite polymorphisms of the factor VIII gene, and to identify the usefulness of intron 13 and intron 22 microsatellite polymorphism for the carrier detection and prenatal diagnosis of hemophilia A in the Korean population. METHODS: Intron 13 and intron 22 microsatellite polymorphisms of the factor VIII gene were analyzed in 30 unrelated Korean mothers of patients with severe hemophilia A using fluorescent PCR. RESULTS: Analysis of intron 13 and intron 22 microsatellite polymorphisms of the factor VIII gene was feasible by the fluorescent-PCR method. The expected heterozygosity rates of intron 13 and intron 22 polymorphisms of the factor VIII gene were 67% and 34%, respectively. Combined analysis of intron 13 and intron 22 polymorphisms revealed heterozygous patterns in 16 (53%) of 30 mothers studied. Using linkage analysis with intron 13 and intron 22 polymorphisms, we have attempted three cases of carrier detection and one cases of prenatal diagnosis in two families of patients with severe hemophilia A. CONCLUSION: These results suggest that flourescent-PCR analysis of the intron 13 and intron 22 microsatellite polymorphisms within the factor VIII gene is very useful in the carrier detection and prenatal diagnosis of hemophilia A in the Korean population.

Carrier detection and prenatal diagnosis of hemophilia A in a Korean population by fluorescent pcr analysis of dinucleotide repeats in intron 13 and intron 22 of the factor VIII gene / 대한산부인과학회지

OBJECTIVE: To set up the methodology for fluorescent PCR analysis of intron 13 and intron 22 microsatellite polymorphisms of the factor VIII gene, and to identify the usefulness of intron 13 and intron 22 microsatellite polymorphism for the carrier detection and prenatal diagnosis of hemophilia A in the Korean population. METHODS: Intron 13 and intron 22 microsatellite polymorphisms of the factor VIII gene were analyzed in 30 unrelated Korean mothers of patients with severe hemophilia A using fluorescent PCR. RESULTS: Analysis of intron 13 and intron 22 microsatellite polymorphisms of the factor VIII gene was feasible by the fluorescent-PCR method. The expected heterozygosity rates of intron 13 and intron 22 polymorphisms of the factor VIII gene were 67% and 34%, respectively. Combined analysis of intron 13 and intron 22 polymorphisms revealed heterozygous patterns in 16 (53%) of 30 mothers studied. Using linkage analysis with intron 13 and intron 22 polymorphisms, we have attempted three cases of carrier detection and one cases of prenatal diagnosis in two families of patients with severe hemophilia A. CONCLUSION: These results suggest that flourescent-PCR analysis of the intron 13 and intron 22 microsatellite polymorphisms within the factor VIII gene is very useful in the carrier detection and prenatal diagnosis of hemophilia A in the Korean population.

Discrepancy variation of dinucleotide microsatellite repeats in eukaryotic genomes

To address whether there are differences of variation among repeat motif types and among taxonomic groups, we present here an analysis of variation and correlation of dinucleotide microsatellite repeats in eukaryotic genomes. Ten taxonomic groups were compared, those being primates, mammalia (excluding primates and rodentia), rodentia, birds, fish, amphibians and reptiles, insects, molluscs, plants and fungi, respectively. The data used in the analysis is from the literature published in the Journal of Molecular Ecology Notes. Analysis of variation reveals that there are no significant differences between AC and AG repeat motif types. Moreover, the number of alleles correlates positively with the copy number in both AG and AC repeats. Similar conclusions can be obtained from each taxonomic group. These results strongly suggest that the increase of SSR variation is almost linear with the increase of the copy number of each repeat motif. As well, the results suggest that the variability of SSR in the genomes of low-ranking species seem to be more than that of high-ranking species, excluding primates and fungi.

Study on association of CTLA4 gene polymorphism with Grave's disease in Guangxi Zhuang nationality population / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the relationship between the polymorphic (AT)n repeats in 3ountranslated region of exon 4 of CTLA4 gene [CTLA4(AT)n] and Graveso disease (GD) in Zhuang nationality population of Guangxi province.</p><p><b>METHODS</b>The studied groups comprised 48 patients with GD and 44 normal controls. Amplification of target DNA was carried out by polymerase chain reaction (PCR). The amplified products were run by 8% polyacrylamide gel electrophoresis, and then followed by 0.1% silver staining. Some of amplified products were sequenced directly.</p><p><b>RESULTS</b>Nineteen alleles of CTLA4 gene microsatellite polymorphism were found in Guangxi Zhuang nationality individuals. The 106 bp long allele was apparently increased in patients with GD of Zhuang nationality but not in healthy controls (P< 0.05).</p><p><b>CONCLUSION</b>CTLA4 gene microsatellite polymorphism is strongly associated with Graveso disease in Zhuang nationality population of Guangxi province. CTLA4(AT)n 106 bp may be the susceptible gene in GD patients of Zhuang nationality in Guangxi; 19 alleles of CTLA4 gene microsatellite polymorphism were found in Guangxi Zhuang nationality individuals.</p>

Genetic Alteration of p16INKA4A Promoter Region in Endometrial Carcinoma / 부인종양

OBJECTIVE: This study was performed to evaluate the status of p16 tumor suppressor gene in 25 endometrial carcinomas (ECs) and to correlate the loss of heterozygosity (LOH) at p16 locus, the presence of inactivating mutations, the methylation status of the promotor, and the expression of p16 protein with clinicopathological parameters. METHODS: Methylation-specific PCR (MSP) distinguishes unmethylated from methylated alleles in a given gene on sequence changes produced after bisulfite treatment of DNA. Allelic losses were determined at two polymorphic dinucleotide repeat microsatellite markers of the p16 gene on chromosome 9p21 that included D9S974 and D9S1748 at CDKN2A. Mutations were analyzed by exons 1 and 2 of p16 PCR-SSCP. Immunohistochemical staining for p16 protein was performed. The associations between genetic alterations of the p16 and the clinicopathological parameters of ECs were evaluated by chi-squared or Fisher's extraction tests. RESULTS: The median age of the 25 cases was 52 years, ranging from 32 to 72. The median tumor size was 3.6 cm, ranging from 0.8 to 9.5 cm. Histologically, the ECs were 21 endometrioid, 2 adenosquamous, 1 secretory and 1 papillary serous types. Nine cases of p16 protein staining were negative or minimal positive in 25 ECs (36%). Allelic losses were found in 6 loci (66.7%) of 5 ECs without p16 protein expression (Fisher's extraction test, p=0.0029), In this study, only 2 of 25 ECs (8%) disclosed mutations. Non-endometrioid (secretory and adenosquamous) carcinomas showed more frequent mutation and methylation than endometrioid carcinomas (p=0.043) and high grades (G3, p=0.018) showed more frequent mutation and methylation than low grade ECs. CONCLUSION: This study suggests that methylation of p16 promoter region seems not to be common (only 9.5% in our present series) and not to be associated with loss of nuclear p16 protein expression. Loss of p16 protein indicates a higher frequency of LOH, which contributes to the development of high grade or aggressive ECs. The mechanism of p16 inactivation is not clear, so other genetic or nongenetic mechanisms for inactivation should be further studied.

Lack of the Association between Microsatellite Polymorphism in Toll-like Receptor 2 Gene and Development of COPD / 결핵및호흡기질환

BACKGROUND: The fact that only 10-20% of chronic cigarette smokers develop chronic obstructive pulmonary disease (COPD) reflects the presence of genetic factors associated with the susceptibility to COPD. Recently, it was reported that the surfactant protein A increases the secretion of matrix metalloprotease 9, which degrades extracellular matrices of the lung, through a Toll-like receptor 2 (TLR2). In this context, possible role of TLR2 in the pathogenesis of COPD was postulated, and a functional dinucleotide repeat polymorphism in intron II of TLR2 was evaluated for any association with COPD. METHOD: Male patients with COPD and male smokers with a normal pulmonary function were enrolled in this study. The number of Guanine-Thymine repeats in intron II of the TLR2 gene were counted. Because the distributions of the repeats were trimodal, the alleles were classified into three subclasses, 12-16 repeats: short (S) alleles; 17-22 repeats: medium length (M) alleles; and 23-27 repeats: long (L) alleles. RESULT: 125 male patients with COPD and 144 age- and gender-matched blood donors with a normal lung function were enrolled. There were no differences in the distribution of each allele subclass (S, M and L) between the COPD and control group (p=0.75). The frequencies of the genotypes with and without each allele subclass in the COPD and control group were similar. CONCLUSION: A microsatellite polymorphism in intron II of TLR2 gene was not associated with the development of COPD in Koreans.

A Family-based and Case-control Association Study of the Dopamine D5 Receptor Gene Polymorphism in Attention Deficit Hyperactivity Disorder / 신경정신의학

OBJECTIVES: Recent genetic studies have suggested a preferential transmission of the Dopamine D5 receptor gene (DRD5) 148bp marker allele. The aim of this study is to test the association between DRD5 and ADHD. METHODS: 106 Korean children with ADHD and their parents were analyzed using the transmission disequilibrium test (TDT) and haplotype-based haplotype relative risk test (HHRR). And also the ADHD children were compared with 212 age and gender matched normal controls. RESULTS: We found the evidence for an association of short alleles of DRD5 dinucleotide repeat polymorphism in both case control and family based studyies. Additionally, we observed some evidence for biased transmission of allele 152 bp and 144 bp. CONCLUSION: Our results lend credence to the notion that the relationship between ADHD and DRD5 is complex. The number of cases and informative transmissions in our study were small, therefore it would be premature to make any conclusions concerning the role of DRD5 in ADHD. Further work is needed to support these findings.

A Family-based and Case-control Association Study of the Dopamine D5 Receptor Gene Polymorphism in Attention Deficit Hyperactivity Disorder / 신경정신의학

OBJECTIVES: Recent genetic studies have suggested a preferential transmission of the Dopamine D5 receptor gene (DRD5) 148bp marker allele. The aim of this study is to test the association between DRD5 and ADHD. METHODS: 106 Korean children with ADHD and their parents were analyzed using the transmission disequilibrium test (TDT) and haplotype-based haplotype relative risk test (HHRR). And also the ADHD children were compared with 212 age and gender matched normal controls. RESULTS: We found the evidence for an association of short alleles of DRD5 dinucleotide repeat polymorphism in both case control and family based studyies. Additionally, we observed some evidence for biased transmission of allele 152 bp and 144 bp. CONCLUSION: Our results lend credence to the notion that the relationship between ADHD and DRD5 is complex. The number of cases and informative transmissions in our study were small, therefore it would be premature to make any conclusions concerning the role of DRD5 in ADHD. Further work is needed to support these findings.

Diagnosis of hemophilia A by a combination of St14(DXS52) VNTR polymorphism and (CA)n repeat polymorphism within FVIII gene / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To improve the accuracy and the diagnostic rate of gene diagnosis and prenatal gene diagnosis for hemophilia A (HA) families.</p><p><b>METHODS</b>Linkage analysis was performed by using St14(DXS52) VNTR polymorphism and intron 13 (CA)n repeat polymorphism of the factor VIII gene among HA families for indirect diagnosis.</p><p><b>RESULTS</b>The diagnostic rates using linkage analysis based upon one of the above mentioned two polymorphic loci among 9 HA families were 66.7% and 66.7%, respectively. The diagnostic rate rose to 88.9% by using a combination of the two polymorphic loci. Prenatal gene diagnoses were performed for 4 HA families. A wrong prenatal diagnosis which may happen when linkage analysis was performed by using only St14 VNTR was monitored.</p><p><b>CONCLUSION</b>The rapid and accurate gene diagnosis and prenatal gene diagnosis could be performed by a combination of the two polymorphic loci for about 90% HA families.</p>

Estrogen Receptor Dinucleotide Polymorphism in Patients with Endometriosis / 대한산부인과학회잡지

OBJECTIVE: To explore the association of the estrogen receptor dinucleotide repeat polymorphism with the risk of endometriosis. DESIGN: Case-control study. METHODS: One hundred fifty-one women with surgically or histologically diagnosed endometriosis of stages I-IV (ASRM, 1997) were recruited, and 137 patients with no evidence of endometriosis by laparoscopy or laparotomy served as control. Dinucleotide repeat polymorphism of the estrogen receptor gene was assessed by fluorescent PCR with gene scan analysis. Allele frequencies of dinucleotide repeat polymorphism of the estrogen receptor gene were evaluated. RESULTS: Fifteen alleles of the estrogen receptor dinucleotide repeat polymorphism were found in subjects: from 12 repeats to 27 repeats except 26 repeats. There was no statistically significant difference in the allele distribution of dinucleotide repeat polymorphism between patients with endometriosis and controls. However, patients with stage I or II endometriosis (n=51) showed a higher incidence of alleles with fewer (TA)n repeats (12-15 repeats) compared with controls (67.6% vs 52.9%, p=0.010, odds ratio=1.860). CONCLUSION: These results suggest that dinucleotide repeat polymorphism of the estrogen receptor gene is associated with the risk of minimal or mild endometriosis in the Korean population.

The inactive X chromosome in the human female is enriched in 5-methylcytosine to an unusual degree and appears to contain more of this modified nucleotide than the remainder of the genome.

By employing a procedure that combines ELISA and photoacoustic spectroscopy, we have examined the content of 5-methylcytosine (m(5)C) in DNA of individuals who differed from one another in the number of X chromosomes in their genomes. The results show that the human inactive X chromosome (Xi) contains very high amounts of this modified nucleotide. We estimate that in the 46,XX female there is more m(5)C in Xi (~ 3.6 x 10(7)) than in all the remaining chromosomes put together (~ 2.1 x 10(7)). Our results also suggest that nearly one-fifth of all cytosines in Xi are methylated and that, in addition to CpG methylation, there is extensive non-CpG methylation as well.

The Impact of Gene Polymorphisms of Interleukin-10 and Interferon-gamma on the Clinical Courses of Renal Transplant Patients in Korea / 대한신장학회잡지

BACKGROUND: The single nucleotide polymorphism (SNP) of interleukin-10 and the variable number of tandem repeat (VNTR) of CA dinucleotide of Interferon-gamma are reported to have an influence on the production of IL-10 and IFN-gamma respectively. The aims of this study are to investigate the gene polymorphisms of IL-10 and IFN-gamma in Korean renal transplant patients and to assess their impacts on the clinical courses of renal allografts. METHODS: The one hundred eighty-five patients who received renal allografts and were followed for more than 5 months from 1991 to May 2000 in Kangdong Sacred Heart Hospital, and ninety-eight normal healty controls were investigated. Three SNPs in promoter region of IL-10 gene were assayed by PCR-RFLP. The (CA) dinucleotide repeat polymorphism of IFN-gamma were assessed by evaluation of size of PCR products. RESULTS: Allele*2 and allele*3 were major alleles of IFN-gamma in our study and there was no significant difference of alleleic and genotypic distribution between recipient and control group. The -592*A and -592*C in the IL-10 promotor region were tightly linked to -819*T and -819*C, respectively. The frequency of -1082*G/*A genotype of recipent group was 7.0% and smaller than that of control group (17.3%, p=0.02). The *G/*G genotype (IL-10 high producer) was absent in all our study subjects, which was quite different from Western studies. IFN-gamma and IL-10 gene polymorphisms had no impact on the incidence and severity of acute rejection, and long term graft fucntion after transplantation. CONCLUSION: Unlike IFN-gamma the SNPs of IL-10 promoter were quite different from those in Western patients. The frequency of -1,082*G/*A genotype of IL-10 was smaller in recipient group. In conclusion, the polymorphisms of IL-10 and IFN-gamma had no impact on the clinical courses of renal allografts under the current therapeutic strategies.

Carrier detection in non-deletional Duchenne/Becker muscular dystrophy families using polymorphic dinucleotide (CA) repeat loci of dystrophin gene.

BACKGROUND & OBJECTIVES: Carrier detection and prenatal diagnosis is of great importance for families with one or more sons affected with Duchenne/Becker muscular dystrophy (D/BMD). In about 35-40 per cent of these patients, the causative mutation does not involve gross rearrangement in the structure of dystrophin gene. In these non-deletional families, genetic counselling can be provided only by linkage analysis. The aim of the present study was to determine the carrier status of female relatives in north Indian families with non-deletional D/BMD using highly polymorphic intragenic dinucleotide (CA) repeat markers. METHODS: Six short tandem repeats (STRs) spanning 5' (1), central (4) and 3' regions of the dystrophin gene were used to analyse 14 unrelated families comprising 68 individuals with 12 female siblings at risk of being carriers. RESULTS: Five female siblings inherited at risk STR haplotype, six inherited normal haplotype and one had meiotic recombination. The intragenic recombinations were observed in three families at the central region STR loci and in one family between the proximal and central regions of the gene. INTERPRETATION & CONCLUSIONS: Our study suggested that at least 6 STR markers spanning 5', central and 3' regions of the dystrophin gene are essential to ascertain one or more informative loci and to rule out recombinations in non-deletional D/BMD families for carrier analysis.

Association of(G-T)n Dinucleotide Repeat Polymorphism of 5'-Flanking Region of TIGR/MYOC with Normal-Tension Glaucoma and Steroid-Induced Glaucoma

PURPOSE: We investigated whether TIGR/MYOC, a candidate gene for the primary open angle glaucoma(POAG) is also involved in the pathogenesis of normal tension glaucoma(NTG) and steroid-induced glau-coma(SIG). METHODS: Genomic DNA was extracted from the peripheral blood samples collected from 72 normal volunteers and 60 POAG, 47 NTG, 61 SIG patients. The genotype distribution of dinucleotide repeat polymorphism, (G-T)n microsatellite located 249 bp upstream of transcription start site was determined by direct sequencing of the Polymerase Chain Reaction(PCR) product. RESULTS: We found 6 alleles in the (G-T)n microsatellite of TIGR/MYOC ranging from 12 to 17, which differ slightly from that of previous reports. There was no obvious difference in the genotype distribution and allele frequency between the POAG group and the control group. However, a significant association of the microsatellite marker with SIG and, to a lesser extent, with NTG was observed. A significant increase in the frequency of (G-T)13/(G-T)13 genotype and a concomitant decrease in the frequency of (G-T)13/(G-T)14 genotype was seen in both the NTG and SIG group compared to that of the control group. In the SIG group, a significant decrease in the frequency of (G-T)14 allele was also observed compared to the control group, although the decrease did not contribute to the increase in the frequency of the allele. CONCLUSIONS: These findings suggest that a polymorphism in the 5 flanking region of the TIGR/MYOC is associated with patients with NTG and SIG.

Microsatellite Instability in Non-Small Cell Lung Cancer / 결핵

PURPOSE: Microsatellite instability (MSI) is frequently used as an indicative of microsatellite mutator phenotype (MMP) tumors. MSI has been observed in a fraction of non-small cell lung cancer (NSCLC). However, its role in tumorigenesis of NSCLC remains unknown. We evaluated the frequency and pattern of MSI in NSCLC, and compared the clinical parameters of MSI-positive tumors with those of MSS (microsatellite stable) tumors. MATERIALS AND METHODS: Twenty surgically resected NSCLCs were analyzed for 15 microsatellite markers located at chromosome 3p and 9p. Patients' peripheral blood lymphocytes were used as the source of the normal DNA. RESULTS: 1) Of 20 cases, 8 (40%) demonstrated MSI. 2) Instability observed more commonly in tri- and tetra-nucleotide repeats rather than dinucleotide repeats. In all cases, instability appeared as a shift of individual allelic bands. 3) LOH was observed in 10 (50%) of 20 tumors analyzed. 4) Of 20 cases, MSI-H tumor (showing MSI in the majority of markers) was absent. There were 5 MSI-L tumors (showing MSI in a greater than 10% of markers). 5) No significant difference was observed between MSI-L tumors and MSI-negative tumors in clinicopathologic features such as pack-year history of smoking, histologic subtype, and the stage of disease. There was also no significant difference in the incidence of LOH according to the status of MSI. CONCLUSION: These data strongly suggest that MSI has different roles in lung and colon cancer. MMP pathway appears far less important in the tumorigenesis of NSCLC, caused mainly by cigarette smoke, with little familial tendency.

Carrier Detection and Prenatal Diagnosis of Hemophilia A in a Korean Population by Analysis of Two Variable Dinucleotide Tandem Repeats within the Factor VIII Gene / 대한산부인과학회잡지

We have undertaken this study to identify the usefulness of two variable dinucleotide tandem repeats within the factor VIII gene for carrier detection and prenatal diagnosis of hemophilia A in the Korean population. We have analyzed these polymorphisms in 50 unrelated Korean mothers of patients with severe hemophilia A, using polymerase chain reaction. The expected heterozygosity rates of the intron 13 and intron 22 dinucleotide repeats were 56% and 40%, respectively. Analysis of the intron 13 and intron 22 dinucleotide repeats revealed heterozygous patterns in 29(58%) and 17(34%) of 50 mothers studied, respectively. The combined overall informativity of the intron 13 and intron 22 dinucleotide repeats was 68%. Using linkage analysis with the intron 13 dinucleotide repeats, we have attempted three cases of carrier detection and two cases of prenatal diagnosis in two families of patients with severe hemophilia A. Two pregnant women were diagnosed as carriers, and the other patients as non-carrier Prenatal diagnosis revealed an unaffected male in one fetus, and an unaffected female in another fetus. This data demonstrated that the analysis of the intron 13 and intron 22 dinucleotide repeats very useful in the carrier detection and prenatal diagnosis of hemophilia A in the Korean population.