The Prader-Willi syndrome (PWS) is a human imprinting disorder resulting from genomic alterations that inactivate imprinted, paternally expressed genes in human chromosome region 15q11-q13. This genetic condition appears to be a contiguous gene syndrome caused by the loss of at least 2 of a number of genes expressed exclusively from the paternal allele, including SNRPN, MKRN3, MAGEL2, NDN and several snoRNAs, but it is not yet well known which specific genes in this region are associated with this syndrome. Prader-Will-Like syndrome (PWLS) share features of the PWS phenotype and the gene functions disrupted in PWLS are likely to lie in genetic pathways that are important for the development of PWS phenotype. However, the genetic basis of these rare disorders differs and the absence of a correct diagnosis may worsen the prognosis of these individuals due to the endocrine-metabolic malfunctioning associated with the PWS. Therefore, clinicians face a challenge in determining when to request the specific molecular test used to identify patients with classical PWS because the signs and symptoms of PWS are common to other syndromes such as PWLS. This review aims to provide an overview of current knowledge relating to the genetics of PWS and PWLS, with an emphasis on identification of patients that may benefit from further investigation and genetic screening.
Alleles ; Chromosomes, Human ; Diagnosis ; Genetic Testing ; Genetics* ; Humans ; Phenotype ; Prader-Willi Syndrome* ; Prognosis ; RNA, Small Nucleolar ; snRNP Core Proteins

The Prader-Willi syndrome (PWS) is a human imprinting disorder resulting from genomic alterations that inactivate imprinted, paternally expressed genes in human chromosome region 15q11-q13. This genetic condition appears to be a contiguous gene syndrome caused by the loss of at least 2 of a number of genes expressed exclusively from the paternal allele, including SNRPN, MKRN3, MAGEL2, NDN and several snoRNAs, but it is not yet well known which specific genes in this region are associated with this syndrome. Prader-Will-Like syndrome (PWLS) share features of the PWS phenotype and the gene functions disrupted in PWLS are likely to lie in genetic pathways that are important for the development of PWS phenotype. However, the genetic basis of these rare disorders differs and the absence of a correct diagnosis may worsen the prognosis of these individuals due to the endocrine-metabolic malfunctioning associated with the PWS. Therefore, clinicians face a challenge in determining when to request the specific molecular test used to identify patients with classical PWS because the signs and symptoms of PWS are common to other syndromes such as PWLS. This review aims to provide an overview of current knowledge relating to the genetics of PWS and PWLS, with an emphasis on identification of patients that may benefit from further investigation and genetic screening.
Alleles ; Chromosomes, Human ; Diagnosis ; Genetic Testing ; Genetics* ; Humans ; Phenotype ; Prader-Willi Syndrome* ; Prognosis ; RNA, Small Nucleolar ; snRNP Core Proteins

PURPOSE: Prader-Willi Syndrome(PWS) is caused by absence of paternal contributions of the chromosome region 15q11-q13. To detact this region, high resolutional cytogenetic analysis, FISH with probe at PWS critical region or microsatellite polymorphism can be used. The gene for the small nuclear ribonucleoprotein polypeptide N(SNRPN) is not expressed in patients with PWS. We conducted molecular analysis with RT-PCR with SNRPN primers to find out more useful diagnostic tool in PWS. METHODS: Four patients with obesity and other characteristics of PWS were studied. The exprssion of SNRPN and control gene were studed by RT-PCR from peripheral lymphocytes. RESULTS :The SNRPN expression in reverse transcribed RNA from blood were easily detected in normal control but not in patients with suspected Parder-Willi Syndrome. CONCLUSION: We conclude that SNRPN expression study is a useful diagnostic method for detection of Prader-Willi Syndrome.
Cytogenetic Analysis ; Humans ; Lymphocytes ; Microsatellite Repeats ; Obesity ; Pathology, Molecular* ; Prader-Willi Syndrome* ; Ribonucleoproteins, Small Nuclear ; RNA ; snRNP Core Proteins*

PURPOSE: To detect microdeletion of 15q11-13 region, high resolution cytogenetic analysis or FISH with probe at Prader-Willi syndrome region can be used. We tried to evaluate whether FISH with SNRPN is a more effective method than G-banding microscope in the diagnosis of Prader-Willi syndrome. MEHTODS: Peripheral blood sampling was done on five patients who we suspected of Prader-Willi syndrome clinically and lymphocytes from peripheral blood sampling were cultured. G-banding microscope was used to detect the microdeletion in chromosome 15 and FISH with SNRPN probe was used to detect signal defect in band q11-q13 in chromosome 15. RESULTS: There was a fluorescent signal defect in band 15 q11-q13 in one of chromosome 15 in 4 children with FISH method and only one patient was diagnosed with Prader-Willi syndrome with G-banding microscope. CONCLUSION: FISH analysis is more accurate, objective, and time saving than G-banding microscope, therefore it can be considered as a more adequate screening test for the diagnosis of Prader-Willi syndrome.
Child ; Chromosomes, Human, Pair 15 ; Cytogenetic Analysis ; Diagnosis* ; Fluorescence* ; Humans ; Lymphocytes ; Mass Screening ; Prader-Willi Syndrome* ; snRNP Core Proteins

BACKGROUND: The histogenesis and interrelationship of the various types of germ cell tumors (GCTs) have been proposed. Dysgerminoma/seminoma (D/S) is a primitive GCT that has not acquired the potential for further differentiation, whereas other types of GCTs are in a dynamic process of differentiation towards a somatic or extraembryonal direction. A primordial germ cell giving rise to a GCT undergoes a developmentally regulated erasure and resetting of imprinted genes, but changes in the imprinting pattern in GCTs as the tumor differentiates have not been well defined. We aimed to investigate the changes of the SNRPN methylation pattern between the germinomas and non-germinomatous GCTs, as compared with the somatic methylation pattern. METHODS: We used formalin-fixed paraffin-embedded tissue sections of 97 GCTs (18 Ds, 21 Ss, 17 yolk sac tumors (YSTs), 19 immature teratomas, and 22 mature teratomas). DNA methylation was evaluated after bisulfite modification, PCR amplification, and restriction enzyme digestion. RESULTS: The SNRPN methylation pattern was changed in 53/74 (71.6%) of GCTs as non-somatic patterns. There were significant differences in the methylation pattern between the germinomas and non-germinomatous GCTs, the GCTs being frequently hypo- methylated in Ds/Ss (73.3%), in contrast to the frequent hypermethylation seen in the YSTs and teratomas (47.7%, p<0.05). CONCLUSIONS: The methylation status of an imprinting gene may be involved in the mechanism causing cellular differentiation and tumorigenesis of GCTs.
Carcinogenesis ; Digestion ; DNA Methylation ; Endodermal Sinus Tumor ; Genomic Imprinting ; Germ Cells* ; Germinoma ; Humans* ; Methylation* ; Neoplasms, Germ Cell and Embryonal* ; Polymerase Chain Reaction ; Ribonucleoproteins, Small Nuclear* ; snRNP Core Proteins ; Teratoma

Prader-Willi syndrome is caused by absence of paternal contribution of chromosome region 15q11-q13. PWS is clinically suspected and can be confirmed by laboratory tests. It is accepted that DNA methylation analysis is very useful screening test and FISH with specific probe can be used for deletion detection for PWS. In clinically suspected PWS patients, we conducted two genetic tests, FISH with SNRPN probe and SNRPN expression study with RT-PCR. We found discordance in one patient. This PWS male presented with severe obesity, hypogonadism and typical appearance with the history of neonatal hypotonia and feeding problems. The FISH showed the microdeletion in 15q11-q13 as expected, but the result of SNRPN expression was positive. We reviewed FISH and observed normal cells without deletion. Methylation analysis is not sensitive enough to identify cases of mosaic PWS. So, when the molecular screening is negative, precise clinical examination is essential and other cytogenetic analysis like FISH should be combined.
Cytogenetic Analysis ; DNA Methylation ; Humans ; Hypogonadism ; In Situ Hybridization, Fluorescence* ; Male ; Mass Screening ; Methylation ; Mosaicism* ; Muscle Hypotonia ; Obesity, Morbid ; Prader-Willi Syndrome ; snRNP Core Proteins

BACKGROUNDSmD1-amino-acid 83-119 peptide (SmD183-119) is the major epitope of Smith (Sm) antigen, which is specific for adult systemic lupus erythematosus (SLE). The anti-SmD183-119 antibody has exhibited higher sensitivity and specificity than anti-Sm antibody in diagnosing adult SLE. However, the utility of anti-SmD183-119antibodies remains unclear in children with SLE (cSLE). This study aimed to assess the characteristics of anti-SmD183-119antibody in the diagnosis of cSLE.

METHODSSamples from 242 children with different rheumatological and immunological disorders, including autoimmune diseases (SLE [n = 46] and ankylosing spondylitis [AS, n = 11]), nonautoimmune diseases (Henoch-Schonlein purpura [HSP, n = 60], idiopathic thrombocytopenia purpura [n = 27], hematuria [n = 59], and arthralgia [n = 39]) were collected from Shanghai Children's Medical Center from March 6, 2012 to February 27, 2014. Seventy age- and sex-matched patients were enrolled in this study as the negative controls. All the patients' sera were analyzed for the anti-SmD183-119, anti-Sm, anti-U1-nRNP, anti-double-stranded DNA (dsDNA), anti-nucleosome, anti-SSA/Ro60, anti-SSA/Ro52, anti-SSB, anti-Scl-70, and anti-histone antibodies using the immunoblotting assay. The differences in sensitivity and specificity between anti-SmD183-119 and anti-Sm antibodies were compared by Chi-square test. The correlations between anti-SmD183-119and other auto-antibodies were analyzed using the Spearman's correlation analysis. A value of P< 0.05 was considered statistically significant.

RESULTSThirty-six out of 46 patients with cSLE were found to be positive for anti-SmD183-119, while 12 patients from the cSLE cohort were found to be positive for anti-Sm. Compared to cSLE, it has been shown that anti-SmD183-119 was only detected in 27.3% of patients with AS and 16.7% of patients with HSP. In comparison with anti-Sm, it has been demonstrated that anti-SmD183-119 had a higher sensitivity (78.3% vs. 26.1%, χ2 = 25.1, P< 0.05) and a lower specificity (90.8% vs. 100%, χ2 = 13.6, P< 0.05) in the diagnosis of cSLE. Further analysis revealed that anti-SmD183-119antibodies were positively correlated with anti-dsDNA, anti-nucleosome, and anti-histone antibodies in cSLE. Moreover, it has been clearly shown that anti-SmD183-119 was more sensitive than anti-Sm in discriminating autoimmune diseases from nonautoimmune disorders in patients with arthralgia or hematuria.

CONCLUSIONSMeasurement of anti-SmD183-119in patients with cSLE has a higher sensitivity and a marginally lower specificity than anti-Sm. It has been suggested that inclusion of anti-SmD183-119testing in the integrated laboratory diagnosis of cSLE may significantly improve the overall sensitivity in child populations.

Autoantibodies ; immunology ; Autoantigens ; immunology ; Child ; Female ; Humans ; Immune System Diseases ; immunology ; Immunoblotting ; Lupus Erythematosus, Systemic ; immunology ; Male ; Peptides ; chemistry ; immunology ; snRNP Core Proteins ; immunology

Objective: To study the expression and effect of small nuclear ribonucleoprotein-associated protein B (SNRPB) on proliferation and metastasis of liver cancer tissues and cells. Methods: The bioinformatics database starBase v3.0 and GEPIA were used to analyze the expression of SNRPB in liver cancer tissue and normal liver tissue, as well as the survival and prognosis of liver cancer patients. The expression of SNRPB mRNA and protein in liver cancer cell lines were analyzed by qRT-PCR and Western blot. RNA interference technique (siRNA) was used to determine SNRPB protein expression down-regulation. The proliferation effect on hepatocellular carcinoma cells was observed by MTT assay. Transwell invasion and migration assay was used to detect the changes in the metastatic ability of liver cancer cells after SNRPB down-regulation. Western blot was used to detect the changes of epithelial mesenchymal transition (EMT) markers in liver cancer cells after down-regulation of SNRPB expression. Data were compared between two groups and multiple groups using t-test and analysis of variance. Results: The expression of SNRPB was significantly higher in liver cancer tissue than normal liver tissue, and its expression level was correlated with the prognosis of liver cancer patients. Compared with the immortalized hepatocyte LO(2), the expression of SNRPB was significantly increased in the liver cancer cells (P < 0.01). siRNA-SNRPB had significantly inhibited the expression of SNRPB mRNA and protein in liver cancer cells. MTT results showed that the absorbance value was lower in SNRPB knockdown group than negative control group, and the difference at 96 h after transfection was most significant (P < 0.01). Transwell assay results showed that compared with the negative control group, the SNRPB knockdown group (MHCC-97H: 121.27 ± 8.12 vs. 46.38 ± 7.54; Huh7: 126.50 ± 6.98 vs. 41.10 ± 8.01) invasion and migration (MHCC-97H: 125.20 ± 4.77 vs. 43.18 ± 7.32; Huh7: 132.22 ± 8.21 vs. 38.00 ± 6.78) ability was significantly reduced (P < 0.01) in liver cancer cells. Western blot showed that the expression level of epithelial phenotype marker E-cadherin was decreased after down-regulation of SNRPB, while the expression levels of mesenchymal phenotype markers N-cadherin and vimentin was increased, suggesting that down-regulation of SNRPB inhibited EMT in liver cancer cells. Conclusion: SNRPB expression is significantly increased in liver cancer tissues and cells, and it is involved in regulating the proliferation, metastasis and EMT of liver cancer cells.
Carcinoma, Hepatocellular/genetics* ; Cell Line, Tumor ; Cell Movement ; Cell Proliferation ; Epithelial-Mesenchymal Transition ; Gene Expression Regulation, Neoplastic ; Humans ; Liver Neoplasms/genetics* ; snRNP Core Proteins

OBJECTIVE: To establish two methods by denaturing gradient gel electrophoresis (DGGE) and pyrosequencing for genotyping rs220030 (a SNP in the promoter region of small nuclear ribonucleoprotein polypeptide N, SNRPN). To establish an analytical technique for detecting CpG methylation status by pyrosequencing and to further investigate the feasibility of applying rs220030 to the determination of parental origin allele. METHODS: The rs220030 of 97 blood samples from individuals of Shanghai Han population were genotyped by DGGE, meanwhile the rs220030 of 25 blood samples of them were genotyped by pyrosequencing to compare the two methods in genotyping SNP. Pyrosequencing united bisulfite conversion method was applied to detect CpG methylation status of region upstream rs220030 of two random blood genealogical samples and investigate whether the methylation status was parental related. RESULTS: The rs220030 genotyping results of 97 blood samples detected by DGGE were 20 C homozygote, 29 T homozygote, and 48 C/T heterozygote. Twenty-five blood samples genotyped by pyrosequencing showed the same result with DGGE. The CpG methylation status of region upstream rs220030 of the child was similar to the mother. CONCLUSION Compared with DGGE, pyrosequencing is more accurate, convenient, and suitable for large samples and high throughput SNP genotyping. Pyrosequencing united bisulfite conversion can be used to detect CpG methylation status precisely. It is feasible to apply rs220030 to parental origin allele determination.
Asian People/genetics* ; CpG Islands ; DNA/genetics* ; DNA Methylation ; DNA Primers ; Genomic Imprinting ; Genotype ; Heterozygote ; Humans ; Polymorphism, Single Nucleotide ; Sequence Analysis, DNA ; Sulfites/metabolism* ; snRNP Core Proteins/genetics*

PURPOSE: In general, genetic disorders have the numerical or structural abnormalities of chromosome. There are clinically two different disorders, Prader-Willi syndrome(PWS) and Angelman syndrome(AS), which have the deletion of specific region of 15 chromosome originated from father or mother by genetic imprinting phenomenon. We reported the results of genetic study including DNA methylation analysis and fluorescence in situ hybridization(FISH), in addition to clinical findings. METHODS: We studied 20 patients of PWS and AS diagnosed in pediatric department of Asan Medical Center from 1992 Feb. to 2001 Apr., retrospectively. We analyzed the clinical manifestations of the disorders and performed cytogenetic studies from the peripheral blood. And we the methylation pattern and FISH, using the probe for single nucleotide ribonucleoprotein N(SNRPN) locus within the Prader-Willi/Angelman region (15q11-q13). RESULTS: Among 16 patients of PWS, the age at initial visit was from 3 days to 12 years and the male to female ratio was 1.67:1. Seven patients had the history of intrauterine growth retardation or fetal distress. The chief complaints at initial presentation were classified on age. Under 3 years(n=10), there were hypotonia(4), development delay (3), feeding difficulties(2), and tachycardia(1). Above 3 years(n=6), we found short stature(2), respiratory difficulty(1), seizure(1), obesity(1), and undescended testes(1). DNA methylation study showed the methylation of 15 chromosome originated from paternal chromosome and the microdeletion by FISH was detected in all 12 among 12 patients (100%). In AS(n=4), the sex ratio(M:F) was 3:1 and age at presentation was from 15 months to 6 years. The important sign was severe developmental delay in all patients, combined with mental retardation in one case. Other clinical manifestations were depigmentation of skin and hair(4), prognathism(3), seizure(3), frequent laughing(2), undescended testes(1), hypotonia(1), and hyperactivity(1). FISH study was performed and showed the microdeletion of 15 chromosome in all 4 patients. CONCLUSION: We studied the clinically two different disorders, PWS and AS, with the deletion of same region of 15 chromosome and reported the results of the clinical and genetic analysis based on clinical findings and DNA analysis and FISH study, respectively.
Angelman Syndrome* ; Chungcheongnam-do ; Cytogenetics ; DNA ; DNA Methylation ; Fathers ; Female ; Fetal Distress ; Fetal Growth Retardation ; Fluorescence ; Genomic Imprinting ; Humans ; Intellectual Disability ; Male ; Methylation ; Mothers ; Prader-Willi Syndrome* ; Retrospective Studies ; Ribonucleoproteins ; Skin ; snRNP Core Proteins