Symmetry symptoms in obsessive-compulsive disorder: clinical and genetic correlates

Objective: In obsessive-compulsive disorder (OCD), symmetry-related symptoms may be important. Although clinical correlates of symmetry-related symptoms have been identified in OCD, few data exist on genetic associations. Animal studies indicate involvement of dopamine in symmetry-related behavior, suggesting this may be relevant to analogous symptoms in OCD. Alterations in dopamine may also reflect environmental influences. However, the association of symmetry-related symptomatology, early adversity, and polymorphisms in dopaminergic genes has not been investigated in OCD. Methods: Clinical information and polymorphisms in key dopaminergic genes were compared between OCD patients with primary symmetry symptoms and those without. Results: OCD patients with primary symmetry symptoms comprised 46.6% (n=210) of the sample (n=451), and were older (p < 0.01), had longer illness duration (p < 0.01), higher OCD severity scores (p = 0.01), and greater comorbidity (p < 0.01) than those without. In Caucasians (n=343), genotype frequency differed significantly between groups for ANKK1 rs1800497, with more OCD patients with symmetry symptoms being homozygous for the A2 (CC) genotype (χ2 = 7.296; p = 0.026). Conclusion: Symmetry symptoms have some distinct clinical features and may represent a marker of severity in OCD. However, clinical associations, in combination with the association found with the ANKK1 rs1800497 A2 variant, suggest that primary symmetry symptoms may represent a distinctive clinical and psychobiological profile.

Application of Ion Torrent PGM™ System in Detection of Fetal DNA in Maternal Plasma / 法医学杂志

OBJECTIVE@#To explore the feasibility of detecting of Y-STR of fetal DNA in maternal plasma using Ion Torrent PGM™ System.@*METHODS@#A total of 16 fetal DNA samples from maternal plasmas (8 cases from 38 weeks gestational age and 8 ones from 12 weeks) were prepared and a multiplex assay with 7 STR loci (DYS390, DYS391, DYS393, DYS438, DYS437, DYS456, DYS635) was designed for multiplex-PCR amplification. Using Ion Torrent PGM™ System, the results of Y-STR sequences and capillary electrophoresis were obtained and compared.@*RESULTS@#Y-STR specific alleles were detected in the maternal plasma of all the pregnant women having male babies of second and third trimester, which were higher than that detected by capillary electrophoresis. Consistent Y-STR genotypes were observed between fetal DNA from maternal plasma and genomic DNA from the newborn babies.@*CONCLUSION@#Based on Ion Torrent PGM™ System, the prenatal Y-STR detection method may provide a high-sensitive and high-throughput choice for prenatal STR detection in forensic testing.

Correlations between major risk factors and closely related Mycobacterium tuberculosis isolates grouped by three current enotyping procedures: a population-based study in northeast Mexico

The characteristics of tuberculosis (TB) patients related to a chain of recent TB transmissions were investigated. Mycobacterium tuberculosis (MTB) isolates (120) were genotyped using the restriction fragment length polymorphism-IS6110 (R), spacer oligotyping (S) and mycobacterial interspersed repetitive units-variable number of tandem repeats (M) methods. The MTB isolates were clustered and the clusters were grouped according to the similarities of their genotypes. Spearman’s rank correlation coefficients between the groups of MTB isolates with similar genotypes and those patient characteristics indicating a risk for a pulmonary TB (PTB) chain transmission were ana- lysed. The isolates showing similar genotypes were distributed as follows: SMR (5%), SM (12.5%), SR (1.67%), MR (0%), S (46.67%), M (5%) and R (0%). The remaining 35 cases were orphans. SMR exhibited a significant correlation (p < 0.05) with visits to clinics, municipalities and comorbidities (primarily diabetes mellitus). S correlated with drug consumption and M with comorbidities. SMR is needed to identify a social network in metropolitan areas for PTB transmission and S and M are able to detect risk factors as secondary components of a transmission chain of TB.

Genotypes of pathogenic Leptospira spp isolated from rodents in Argentina

Leptospirosis is the most widespread zoonosis in the world and significant efforts have been made to determine and classify pathogenic Leptospira strains. This zoonosis is maintained in nature through chronic renal infections of carrier animals, with rodents and other small mammals serving as the most important reservoirs. Additionally, domestic animals, such as livestock and dogs, are significant sources of human infection. In this study, a multiple-locus variable-number tandem repeat analysis (MLVA) was applied to genotype 22 pathogenic Leptospira strains isolated from urban and periurban rodent populations from different regions of Argentina. Three MLVA profiles were identified in strains belonging to the species Leptospira interrogans (serovars Icterohaemorrhagiae and Canicola); one profile was observed in serovar Icterohaemorrhagiae and two MLVA profiles were observed in isolates of serovars Canicola and Portlandvere. All strains belonging to Leptospira borgpetersenii serovar Castellonis exhibited the same MLVA profile. Four different genotypes were isolated from urban populations of rodents, including both mice and rats and two different genotypes were isolated from periurban populations.

Insulin-like growth factor 1 gene (CA)n repeats and a variable number of tandem repeats of the insulin gene in Brazilian children born small for gestational age

OBJECTIVE: To investigate the influence of (CA)n repeats in the insulin-like growth factor 1 gene and a variable number of tandem repeats of the insulin gene on birth size in children who are small or adequate-sized for gestational age and to correlate these polymorphisms with serum insulin-like growth factor 1 levels and insulin sensitivity in children who are small for gestational age, with and without catch-up growth. PATIENTS AND METHODS: We evaluated 439 infants: 297 that were adequate-sized for gestational age and 142 that were small for gestational age (66 with and 76 without catch-up). The number of (CA)n repeat in the insulin-like growth factor 1 gene and a variable number of tandem repeats in the insulin gene were analyzed using GENESCAN software and polymerase chain reaction followed by enzymatic digestion, respectively. Clinical and laboratory data were obtained from all patients. RESULTS: The height, body mass index, paternal height, target height and insulin-like growth factor 1 serum levels were higher in children who were small for gestational age with catch-up. There was no difference in the allelic and genotypic distributions of both polymorphisms between the adequate-sized and small infants or among small infants with and without catch-up. Similarly, the polymorphisms were not associated with clinical or laboratory variables. CONCLUSION: Polymorphisms of the (CA)n repeats of the insulin-like growth factor 1 gene and a variable number of tandem repeats of the insulin gene, separately or in combination, did not influence pre- or postnatal growth, insulin-like growth factor 1 serum levels or insulin resistance. .

Herramienta web para la clasificación de microsatélites polimórficos en genomas bacterianos / Web Tool for classfication of polymorphic microsatellites in bacteria genomes

Las secuencias repetidas en tándem, específicamente los mini y micro satélites, han demostrado ser muy eficaces en la clasificación de bacterias patogénicas como B. anthracis, M. tuberculosis y P. aeruginosa, entre otras. En humanos es manifiesta su participación estando relacionados con más de ochenta enfermedades, gran parte de ellas de tipo neurodegenerativas, musculares y algunos tipos de cáncer. La herramienta web que presentamos es el resultado de la detección computacional de estas secuencias en genomas bacterianos completos y su correspondiente anotación en la estructura genómica de acuerdo a las diferentes regiones donde estos se localizan. La herramienta tiene como fin primario brindar un sistema relacional que permita al investigador ubicar los microsatélites de diferentes especies bacterianas, con más de un genoma secuenciado para inferir su posible carácter polimórfico, dentro del contexto de la estructura genómica y así proveer un primer acercamiento al rol putativo que los microsatélites desempeñan desde el punto de vista funcional. La herramienta se puede aplicar no solo en estudios taxonómicos y epidemiológicos sino en la detección de posibles relaciones de estas secuencias con las funciones moleculares, procesos biológicos y, en última instancia, las diversas formas de evolución de estas especies. El sitio web brinda el servicio de consultas a la base de datos de microsatélites bacterianos de acuerdo al sistema de tablas relacionales y atributos propios de las mismas. Cuenta además con los servicios típicos de un sitio con estas características como: sistema de autenticación, foro, encuestas, enlaces y documentación sobre la metodología empleada y del tema en cuestión(AU)

The tandem repeat sequences, especially mini and microsatellites, have proven to be very effective in classification of pathogenic bacteria such as B. anthracis, M. tuberculosis and P. aeruginosa, among others. In human beings it is manifest its participation, being related with over eighty diseases, nearly all neurodegenerative and muscular, and some kinds of cancer. The web tool we are offering here is the result of computational detection of these sequences in whole bacteria genomes, and its respective annotation in the genomic structure according to the different regions where they are localized. The primary goal of this tool is to offer a relational system that allows mapping the microsatellites of bacterial species, all of them with more than one genome sequenced to infer their possible polymorphic character, in the context of genomic structure and thus providing a first approach to the putative role they perform from the functional point of view. The tool can be applied not only in taxonomical and epidemiological studies but in the detection of possible relationships of these sequences with the molecular functions, the biological processes and, as a last resort, the different forms of these species evolution. The web site offers the service of queries to the bacterial microsatellites database according to the related tables and its inherent attributes. It also has the typical services of this kind of site like: logging system, forum, polls, links and documentation about the employed methodology and the topic(AU)

Genome association analysis for pregnancy status following parturition in crossbred beef cattle / Estudo de associação genômica de prenhez pós-parto em vacas de corte

The aim of this study was to evaluate genetic diversity of nine molecular markers, six short tandem repeats - STRs (BM4325, BMS3004, ILSTS002, IDVGA51, HEL5, AFZ1) and three single nucleotide polymorphisms (SNPs; LepSau3A1 A-B, LepSau3A1 1-2, and FSHRAlu1), linked to genes involved in reproductive function and their possible effect on reproductive performance. For this purpose, 81 crossbred beef cows were used in this study. The animals were classified into two groups (fertile and sub-fertile cows) based on their pregnancy status after two breeding seasons. High genetic diversity level was observed highlighted by the polymorphic content information ranging 0.23 to 0.87 and expected heterozygosity from 27 to 89%, with an average of 62%. Alleles BM4325 103, BMS3004 129, ILSTS002 137, IDVGA51 177, LEPSau3A1 A, LEPSau3A1 1, HEL5 149, AFZ1 119 and FSHRAlu1 G presented high frequencies. Two STRs (IDVGA51 and ILSTS002), linked to Leptin and LH genes, respectively, were associated to reproductive performance. These data support previous findings suggesting the potential use of IDVGA51 and ILSTS002 STRs for reproductive performance selection.

Foi avaliada a diversidade genética de nove marcadores moleculares, dos quais seis do tipo short tandem repeats - STR (BM4325, BMS3004, ILSTS002, IDVGA51, HEL5, AFZ1) e três do tipo single nucleotide polymorphisms - SNPs (LepSau3A1 A-B, LepSau3A1 1-2 e FSHRAlu1), ligados a genes envolvidos na reprodução e seus efeitos na performance reprodutiva. Foram examinadas amostras de sangue de 81 vacas sem raça definida, os animais foram classificados em dois grupos (vacas férteis e subférteis) baseado nas taxas de prenhez de duas estações reprodutivas. Alto nível de diversidade genética foi observado, revelando alto conteúdo de informação polimórfica, variando de 0,23 a 0,87 e heterozigosidade esperada de 27 a 89% com 62% em média. Os alelos mais frequentes foram BM4325 103*, BMS3004 129*, ILSTS002 137*, IDVGA51 177*, LEPSau3A1 A, LEPSau3A1 1, HEL5 149*, AFZ1 119* e FSHRAlu1 G. Os marcadores IDVGA51 e ILSTS002, ligados aos genes da leptina e LH, respectivamente, foram associados a performance reprodutiva. Esses dados suportam achados prévios que sugerem o potencial uso desses marcadores na seleção de animais com maior performance reprodutiva.

Spoligotyping and variable number tandem repeat analysis of Mycobacterium bovis isolates from cattle in Brazil

We performed spoligotyping and 12-mycobacterial interspersed repetitive unit-variable number tandem repeats (MIRU-VNTRs) typing to characterise Mycobacterium bovis isolates collected from tissue samples of bovines with lesions suggestive for tuberculosis during slaughter inspection procedures in abattoirs in Brazil. High-quality genotypes were obtained with both procedures for 61 isolates that were obtained from 185 bovine tissue samples and all of these isolates were identified as M. bovis by conventional identification procedures. On the basis of the spoligotyping, 53 isolates were grouped into nine clusters and the remaining eight isolates were unique types, resulting in 17 spoligotypes. The majority of the Brazilian M. bovis isolates displayed spoligotype patterns that have been previously observed in strains isolated from cattle in other countries. MIRU-VNTR typing produced 16 distinct genotypes, with 53 isolates forming eight of the groups, and individual isolates with unique VNTR profiles forming the remaining eight groups. The allelic diversity of each VNTR locus was calculated and only two of the 12-MIRU-VNTR loci presented scores with either a moderate (0.4, MIRU16) or high (0.6, MIRU26) discriminatory index (h). Both typing methods produced similar discriminatory indexes (spoligotyping h = 0.85; MIRU-VNTR h = 0.86) and the combination of the two methods increased the h value to 0.94, resulting in 29 distinct patterns. These results confirm that spoligotyping and VNTR analysis are valuable tools for studying the molecular epidemiology of M. bovis infections in Brazil.

Algorithms of likelihood ratio for discriminating full sibling from half sibling / 法医学杂志

OBJECTIVE@#To derive the formulae for likelihood ratio calculation in discriminating full sibling from half sibling with single-parent participation or without parent participation.@*METHODS@#Null hypothesis and alternative hypothesis were established for discriminating full sibling from half sibling in two circumstances: two children with single-parent and without parent participation. Conditional probabilities of the genetic evidentiary under null and alternative hypotheses were calculated according to the Bayesian theory. The likelihood ratios were established with the conditional probability under alternative hypothesis division that under null hypothesis, followed with simplification. All the formulae were validated in a real case.@*RESULTS@#While mother or fathers' genetic information available in differentiating full sibling from half sibling, 14 different genotype combinations could be shared by the two detected children at a given locus and the likelihood ratio could be calculated with 5 different formulae respectively. While both parents' genetic information unavailable, 11 different genotype combinations could be shared and the likelihood ratio could be calculated with 7 different formulae respectively. It was validated in a real case that the power of the likelihood ratio method developed for discriminating full sibling from half sibling with single-parent participation was higher than that of the ratio of full sibling index over half sibling index.@*CONCLUSION@#The formulae of likelihood ratio developed are useful for discriminating full sibling from half sibling with single-parent participation or without parent participation.

Prevalence of Drug Resistance-Associated Gene Mutations in Plasmodium vivax in Central China

Resistance of Plasmodium spp. to anti-malarial drugs is the primary obstacle in the fight against malaria, and molecular markers for the drug resistance have been applied as an adjunct in the surveillance of the resistance. In this study, we investigated the prevalence of mutations in pvmdr1, pvcrt-o, pvdhfr, and pvdhps genes in temperate-zone P. vivax parasites from central China. A total of 26 isolates were selected, including 8 which were previously shown to have a lower susceptibility to chloroquine in vitro. For pvmdr1, pvcrt-o, and pvdhps genes, no resistance-conferring mutations were discovered. However, a highly prevalent (69.2%), single-point mutation (S117N) was found in pvdhfr gene. In addition, tandem repeat polymorphisms existed in pvdhfr and pvdhps genes, which warranted further studies in relation to the parasite resistance to antifolate drugs. The study further suggests that P. vivax populations in central China may still be relatively susceptible to chloroquine and sulfadoxine-pyrimethamine.

Calculation of the avuncular index / 法医学杂志

OBJECTIVE@#To introduce the method of avuncular index (AI) calculation.@*METHODS@#Identity by decent coefficient, coancestry coefficient and AI law were employed in identification of uncle-niece relationship, when autosomal STR loci were detected to determine controversial uncle-niece relationship.@*RESULTS@#The results of AI calculation were coincidental using identity by descent coefficien, coancestry coefficient and AI law.@*CONCLUSION@#The results are coincidental using three methods in the different situations. AI index is higher with participation of children's mother.

A primary study of criterion for source identification of gastrointestinal tumor sample with Identifiler multiplex system / 法医学杂志

OBJECTIVE@#To investigate the criterion for source identification of gastrointestinal tumor based on the number of identical allele (IAn) and the number of matched STR locus with 2 identical alleles (A2) in Identifiler system.@*METHODS@#One hundred and five pairs of gastrointestinal tumor samples and homologous normal samples (TN group) were genotyped with Identifiler system. The numbers of STR locus with genotypic alteration (STRGA) in each tumor were determined by comparing the genotype of the matched STR loci in each pair of samples. According to the limited distribution of IAn and A2, 16 different values of IAn was substituted into the published discriminant functions to obtain the cut-off values of IAn and A2 for source identification of tumor sample. Indices including sensitivity (SEN), specificity (SPE), accuracy (AC), positive predictive value (PPV) and negative predictive value (NPV) for distinguishing tumor from an unrelated individual or a full sibling of the patient were calculated. Concordance of the identification results based on the determined criteria and the definite facts were statistically tested with Kappa index.@*RESULTS@#The total frequency of STRGA was 5.46%. There were 31.43% of the 105 tumor samples carried at least one STR locus with STRGA mutation. According to the Fisher discrimination rules, criteria I (IAn>or=23 and A2>or=8) and criteriall (IAn>or=26 and A2>or=11) meet the requirements of distinguishing tumor sample from an unrelated individual or a full sibling of the patient with tumor, respectively. SEN=0.971 0, PPV=1.000 0, PPV=0.891 9 and Kappa=0.923 5, when the criteria were used to determine the specified relatives.@*CONCLUSION@#Criteria I and criteria II were powerful for distinguishing tumor sample from an unrelated individual or a full sibling of the patient with tumor, respectively, when the Identifiler system was adopted for source identification of gastrointestinal tumor sample.

A primary study for criteria of full sibling determination with Identifiler system / 法医学杂志

OBJECTIVE@#To investigate the criteria of the number of identical allele (IAn) and the number of matched STR locus with 2 identical alleles (A2) for full sibling (FS) determination with Identifiler system.@*METHODS@#According to the limited distribution of IAn. and A2, all of the 31 potential values of IAn. were substituted into the published discriminant functions to obtain the cut-off values of IAn and A2 for FS determination, and then 4 different criteria were determined to distinguish 280 FS pairs from 2283 individual pairs, respectively, which had been genotyped with Identifiler system. Cumulative full sibling index (CFSI) of the samples were calculated with ITO method, and 4 different criteria of CFSI (>1, > or =5, > or =20 and > or =100) were also utilized to determinate FS, respectively. Indices including sensitivity (SEN), specificity (SPE), accuracy(AC), positive predictive value(PPV) and negative predictive value (NPV) of the 8 different criteria for FS determination were calculated, respectively. Concordance of FS determination between the criteria based on IAn and A2 and that of CFSI were statistically tested with Kappa index.@*RESULTS@#All the individual pairs, which meet the requirement of (I) IAn > or =15 and A2 > or =4, or (II) IAn > or =16 and A2 > or =3, or (III) IAn > or = 17 and A2 > or =3, or (IV) IAn > or =18 and A2 > or =3, could been concluded as FS. AC, SPE and NPV of the 4 criteria mentioned above and the 4 criteria of CFSI were all over 0.9500 in FS determination. Indices between criterion II and CFSI > or =5, criterion III and CFSI > or =20, criterion IV and CFSI > or =100 were similar with each other and the Kappa indexes of the 3 groups were 0.9049, 0.9204 and 0.9083, respectively. PPV and NPV of criterion III and CFSI > or =20 were all over 0.9500.@*CONCLUSION@#The criterion of IAn > or =17 and A2 > or =3 was feasible and efficient for FS determination with Identifiler system, power of which was similar with the criterion of CFSI > or =20.

Application of multiple polymorphism genetic markers in determination of half sibling sharing a same mother / 法医学杂志

OBJECTIVE@#Determination strategies for half sibling sharing a same mother were investigated through the detection of autosomal and X-chromosomal STR (X-STR) loci and polymorphisms on hypervariable (HV) region of mitochondrial DNA (mtDNA).@*METHODS@#Genomic DNA were extracted from blood stain samples of the 3 full siblings and one dubious half sibling sharing the same mother with them. Fifteen autosomal STR loci were genotyped by Sinofiler kit, and 19 X-STR loci were genotyped by Mentype Argus X-8 kit and 16 plex in-house system. Polymorphisms of mtDNA HV-I and HV-II were also detected with sequencing technology.@*RESULTS@#Full sibling relationship between the dubious half sibling and each of the 3 full siblings were excluded based on the results of autosomal STR genotyping and calculation of full sibling index (FSI) and half sibling index (HIS). Results of sequencing for mtDNA HV-I and HV-II showed that all of the 4 samples came from a same maternal line. X-STR genotyping results determined that the dubious half sibling shared a same mother with the 3 full siblings.@*CONCLUSION@#It is reliable to combine three different genotyping technologies including autosomal STR, X-STR and sequencing of mtDNA HV-I and HV-II for determination of half sibling sharing a same mother.

Source identification of gastric cancer tissue with discriminatory analysis / 法医学杂志

OBJECTIVE@#To evaluate discriminatory analysis on source identification of gastric cancer tissue based on the number of matched STR locus or identical allele.@*METHODS@#Twenty two pairs of fresh gastric cancer tissue and homologous normal tissue were genotyped with Identifiler kit. Frequencies of STR genotypic alteration (STR(GA)), the number of matched STR locus without identical allele (A0), with 1 identical allele (A1), or with 2 identical alleles (A2) and the number of total identical alleles (IAn) were calculated with counting method. A1, A2 and IAn were evaluated with Fisher discriminant functions to determine the source of each gastric cancer tissue. Effectiveness of the identification of gastric cancer tissue was evaluated with error rate.@*RESULTS@#The total frequency STR(GA) was 3.03% (95% CI: 1.46%-4.88%). There were 31.38% (95% CI: 13.86%-54.87%) of gastric cancer samples carried at least one STR locus with STRGA. It was confirmed by the Fisher discriminant functions that each of the 22 gastric cancer tissue samples came from its homologous normal tissue with an error rate of 0.00%.@*CONCLUSION@#Frequency of STRGA in gastric cancer tissue was high. Fisher discriminant functions based on the number of identical alleles or matched STR loci could be a feasible method for source identification of body for gastric cancer tissue samples.

Prevalence of FMS-like tyrosine kinase 3/internal tandem duplication (FLT3/ITD+) in de novo acute myeloid leukemia patients categorized according to cytogenetic risk / Prevalência de duplicação interna in tandem/fms-receptor tirosino-quinase (DIT/FLT3) em pacientes com leucemia mielóide aguda de novo classificados conforme grupos citogenéticos de risco

CONTEXT AND OBJECTIVE: The mechanism involved in leukemogenesis remains unclear and more information about the disruption of the cell proliferation, cell differentiation and apoptosis of neoplastic cells is required. DESIGN AND SETTING: Cross-sectional prevalence study at the Discipline of Hematology, Hospital São Paulo, Universidade Federal de São Paulo. METHODS: We investigated FMS-like tyrosine kinase 3/internal tandem duplication (FLT3/ITD+) in 40 adult patients with de novo acute myeloid leukemia (AML), categorized according to cytogenetic results, from September 2001 to May 2005. RESULTS: Thirteen patients (32.5 percent) were classified as presenting the favorable karyotype, 11 patients (27.5 percent) as an intermediate group, 7 patients (17 percent) as an undefined group and 9 patients (22.5 percent) as the unfavorable group. FLT3/ITD+ was found in 10 patients (25 percent): 3 with FLT3/ITD+ and favorable karyotype; 4 with FLT3/ITD+ and intermediate karyotype; 2 with FLT3/ITD+ and undefined karyotype; and only 1 with FLT3/ITD+ and unfavorable karyotype. Among the patients without FLT3/ITD+, 10 presented favorable karyotype, 8 intermediate, 4 undefined and 8 unfavorable karyotype. The cytogenetic results showed no correlations between FLT3/ITD presence and the prognostic groups (P = 0.13). We found that 2 patients were still alive more than 24 months later, FLT3/ITD+ did not influence the patients' survival rate. CONCLUSION: We found the same frequency of AML with FLT3/ITD+ in both the favorable and intermediate prognosis groups. Only one patient presented AML, FLT3/ITD+ and unfavorable karyotype (the hypothetical worst clinical situation). Therefore, the prognostic advantage of favorable cytogenetics among patients with FLT3/ITD+ remains to be elucidated, for it to be better understood.

CONTEXTO E OBJETIVO: O mecanismo envolvido na leucemogênese permanece obscuro, e maiores informações a respeito das inadequadas proliferação, diferenciação e apoptose das células neoplásicas é fundamental. TIPO DE ESTUDO E LOCAL: Estudo transversal de prevalência na Disciplina de Hematologia e Hemoterapia, Hospital São Paulo, Universidade Federal de São Paulo. MÉTODOS: Nós pesquisamos a duplicação interna in tandem (DIT) do gene FLT3 (Fms-like tyrosine kinase) em 40 pacientes adultos com leucemia mielóide aguda (LMA) de novo, classificados de acordo com os resultados de cariótipo em banda G, de setembro de2001 a maio de 2005. RESULTADOS: Treze pacientes (32,5 por cento) foram classificados como cariótipo favorável, 11 pacientes (27,5 por cento) como grupo intermediário, 7 pacientes (17 por cento) no grupo de prognóstico indefinido e os restantes 9 pacientes (22,5 por cento) foram alocados como desfavorável. A DIT/FLT3 foi encontrada em 10 pacientes (25 por cento), 3 pacientes com DIT/FLT3 e cariótipo favorável, 4 com DIT/FLT3 e cariótipo intermediário, 2 com DIT/FLT3 e cariótipo de prognóstico indefinido e somente 1 paciente com DIT/FLT3 e cariótipo desfavorável. Entre os pacientes sem DIT/FLT3, 10 apresentaram cariótipo favorável, 8 com cariótipo intermediário, 4 com cariótipo de prognóstico indefinido e 8 com cariótipo desfavorável. Não houve correlação entre a presença de DIT/FLT3 e os grupos de prognóstico conforme resultados de citogenética (P = 0,13). No presente estudo encontramos 2 pacientes vivos por mais de 24 meses. A presença de DIT/FLT3 não influenciou a taxa de sobrevida dos pacientes. CONCLUSÃO: Nós observamos a mesma frequência de LMA com DIT/FLT3 tanto no grupo de cariótipo favorável quanto no grupo intermediário e somente um paciente com LMA e DIT/FLT3 e cariótipo desfavorável, hipoteticamente o pior achado clínico. Desta forma, a vantagem prognóstica do cariótipo favorável em pacientes DIT/FLT3 permanece a ser esclarecida ...

Evaluation of the criterion of partial loss of heterozygous in tumor tissues / 法医学杂志

OBJECTIVE@#To evaluate the applicability of partial loss of heterozygous (pLOH) criteria in tumor tissues with Identifiler system.@*METHODS@#Eight thousand four hundred and twenty eight heterozygous loci of the 696 unrelated individuals (UIP) genotyped with Identifiler Kit were randomly paired by locus to construct odds ratio of allelic peak height (or area under allelic curve) according to the given formula. Similarly, odds ratios of allelic peak height (or area under allelic curve) of the 896 heterozygous loci of 77 pairs of tumor and homologous normal tissues (TNP) were also acquired. Curve fitting was performed to determine the distribution of the odds ratio. The proportion of pLOH in two groups was determined with odds ratio less than 0.5 or higher than 2.0. Compared the relevance ratio of allelic peak height and peak area by chi2 test.@*RESULTS@#The odds ratio of both peak height and peak area presented normal distribution in UIP (4214 heterozygous loci pairs) and TNP group (896 heterozygous loci pairs). There was 0.12% of normal heterozygous in UIP group erroneously presumed as pLOH with current criteria (< 0.5 or > 2.0). There was no significantly difference between the calling rate based on two types of odd ratio (P = -0.5632).@*CONCLUSION@#It is feasible to determine the pLOH in tumor tissue with Identifiler system by both peak height and peak area according to the standards of the odds ratio less than 0.5 or higher than 2.0.

Application of number of matched STR loci and identical alleles in individual discrimination of colorectal cancer / 法医学杂志

OBJECTIVE@#To establish a feasible algorithm for individual identification of colorectal cancer tissue by investigating its STR mutation.@*METHODS@#Fifty pairs of fresh colorectal cancer and homologous normal tissues (CR-N group) were genotyped with Identifiler Kit and the mutations generated in cancer tissues were determined. The mutation rates, the numbers of locus matched without identical allele (A0), 1 identical allele (A1), or 2 identical alleles (A2) and the number of total identical alleles (IA(n)) were calculated. Frequency distributions of A0, A1, A2 and IA(n) were compared among CR-N group, unrelated individual pairs (UI group) and full sibling pairs (FS group). Discrimination functions were established for individual identification from tumor tissues with discriminatory analysis.@*RESULTS@#The frequency of STR genotypic alteration (STR(GA)) was 3.33% in the 50 colorectal cancer samples. A1, A1 and IA(n) were fitted to skew distribution in CR-N group, which were significantly different from those in UI or FS group. Based on IA, and A,/A2, discrimination functions were established and validated with an error rate as low as 0.00% for individual identification from colorectal cancer tissue.@*CONCLUSION@#Discrimination functions established in this study could be a feasible method for individual identification of colorectal cancer samples, which usually have a high frequency of STR(GA).

Polymorphic distribution of FUT2/01 in northern Han Chinese population / 法医学杂志

OBJECTIVE@#To investigate the sequence features of FUT2/01 locus and its polymorphic distribution in Chinese population, and to discuss its application potential in forensic medicine.@*METHODS@#The alleles on FUT2/01 locus were amplified by PCR and then were sequenced. Furthermore, polymorphic distribution of the locus was analyzed by polyacrylamide gel electrophoresis. The genotypes were characterized with fluorescence labeling followed by automatic detection system.@*RESULTS@#The sequencing results only showed the length differences which were determined by the tandem repeats variance of the core sequence. There were 9 alleles and 28 genotypes identified from 162 individuals. The discrimination power and excluding probability of paternity were 0.9639 and 0.6266, respectively. In addition, the locus could be genotyped by automatic analysis very well.@*CONCLUSION@#The FUT2/01 locus exhibits high heterozygosity and individual identification power in Chinese Han population, and may be a valuable STR system for application in forensic medicine.

Full sibling identification based on the number of matched STR locus / 法医学杂志

OBJECTIVE@#To establish and evaluate the method of matched locus numbers in full sibling identification.@*METHODS@#Two hundred and eighty full sibling (FS) pairs and 2003 unrelated individual (UI) pairs were genotyped with Identifiler system. The number of locus matched with 0 identical allele (A0), matched with 1 allele (A1) or matched with 2 alleles (A2) were counted and full sibling index (FSI) were calculated based on ITO method. Fisher discriminant functions were established based on the numbers of matched STR locus or FSI. Power of different Fisher discriminant functions was statistically analyzed.@*RESULTS@#The distribution of A1 and A2 in FS group and that of A0 and A1 in UI group were in accord with normal distribution. Contrarily, A0 in FS group and A2 in UI group fitted to skew distribution, respectively. Difference of A1 distribution was not statistically significant in the two groups (P>0.01). The established Fisher discriminant functions based on A0 and A2 for each group were Z(FS)=0.99817A0+4.24442A2-12.77970 and Z(UI)=2.01456A0+1.54658A2-7.28076, respectively, the average error probability of which was as low as 0.0490. The power of discrimination for full sibling showed no statistically significant difference between ITO method and the established Fisher discriminant functions.@*CONCLUSION@#The number of matched STR locus in Identifiler system is a valuable method in full sibling identification. The discriminating power of the established Fisher discriminant functions based on the matched STR locus number is similar with that of classic ITO method in full sibling identification.