Quantitative and qualitative assessment of DNA extracted from saliva for its use in forensic identification.

UNLABELLED: Saliva has long been known for its diagnostic value in several diseases. It also has a potential to be used in forensic science. OBJECTIVE: The objective of this study is to compare the quantity and quality of DNA samples extracted from saliva with those extracted from blood in order to assess the feasibility of extracting sufficient DNA from saliva for its possible use in forensic identification. MATERIALS AND METHODS: Blood and saliva samples were collected from 20 volunteers and DNA extraction was performed through Phenol Chloroform technique. The quantity and quality of isolated DNA was analyzed by spectrophotometery and the samples were then used to amplify short tandem repeat (STR) F13 using the polymerase chain reaction. RESULTS: Mean quantity of DNA obtained in saliva was 48.4 ± 8.2 µg/ml and in blood was 142.5 ± 45.9 µg/ml. Purity of DNA obtained as assessed by the ratio of optical density 260/280, was found to be optimal in 45% salivary samples while remaining showed minor contamination. Despite this positive F13 STR amplification was achieved in 75% of salivary DNA samples. CONCLUSION: Results of this study showed that saliva may prove to be a useful source of DNA for forensic purpose.

Cytokine gene polymorphisms in northern Indian women with recurrent miscarriages.

OBJECTIVE: To determine association of cytokine gene polymorphism with risk for recurrent miscarriages (RM). DESIGN: Retrospective case-control study on northern Indian RM cases versus control subjects. SETTING: Medical facility. PATIENT(S): A total of 200 women with at least three unexplained spontaneous abortions before 20 weeks of gestation. INTERVENTION(S): Subjects were genotyped by polymerase chain reaction amplification followed by restriction digestion and allele-specific oligonucleotides. MAIN OUTCOME MEASURE(S): Detection of pro- and antiinflammatory gene polymorphism genotypes and allele frequencies. RESULT(S): We applied dominant and recessive models of inheritance, showing no association among T(H)2 [interleukin (IL) 10 (592 C/A) and transforming growth factor ß] gene polymorphisms, while significant association was observed between T(H)2 [IL-4 (C590T), IL-6 (G174C), IL-10 (1082A/G and 819C/T)], and T(H)1 [interferon-γ (+874A/T)] with RM compared with control subjects. However, when classification and regression tree analysis was applied, this effect disappeared and demonstrated that IL-10 plays an important role in maintenance of pregnancy. CONCLUSION(S): Interleukin-10 acts as an immunosuppressive by keeping a balance of pro- and antiinflammatory signals that coordinate the satisfactory development of pregnancy, placental growth, and remodeling for favorable pregnancy outcome.

MTHFR gene polymorphism and its relationship with plasma homocysteine and folate in a North Indian population.

There is a paucity of data on the prevalence of elevated homocysteine and its relation with plasma folate and the methylenetetrahydrofolate reductase (MTHFR) gene in the population of North India. This study evaluates MTHFR gene polymorphism and its relationship with plasma homocysteine and folate levels in a healthy North Indian population. The age of the 200 subjects included in this study was in the range 18-73 (mean 39.4) years. The plasma homocysteine level was elevated in 56.5%, and the plasma folate level was low in 49.5% of the subjects. Heterozygous MTHFR gene polymorphism (CT) was present in 15.5%, and homozygous (TT) in 3.5% of the subjects. Age, diet, and MTHFR gene polymorphisms were related to homocysteine level. All the subjects with the TT and 79% with the CT genotype had a high level of plasma homocysteine, whereas 51% with the CC genotype had a high homocysteine level. After adjustment for the effect of covariates, however, homocysteine was not related to MTHFR gene polymorphism.

Use of Multiplex Ligation-Dependent Probe Amplification (MLPA) in screening of subtelomeric regions in children with idiopathic mental retardation.

OBJECTIVE: To detect subtelomeric copy number variations (deletions and duplications) using Multiplex Ligation-Dependent Probe Amplification (MLPA) technique in children with idiopathic mental retardation. METHODS: All children presenting to the genetics out-patient department for evaluation of mental retardation or developmental delay over a period of two years, for whom no identifiable cause could be found by clinical evaluation, karyotyping, neuroimaging and other relevant investigations. RESULTS: In the present study, two cases deletions and one case of duplication were detected amongst 65 cases with idiopathic mental retardation/ global developmental delay. The overall detection rate is 4.6%. The detection rate is higher (13%) in children with facial dysmorphism. CONCLUSION: MLPA for subtelomeric regions is recommended for evaluation of children with idiopathic mental retardation/ global developmental delay were included in the study.

Fragile histidine triad (FHIT) gene and its association with p53 protein expression in the progression of gall bladder cancer.

OBJECTIVE: Present study deals with LOH and MSI in FHIT gene and p53 expression in GBC, CC, XGC, and normal GB to elucidate the role of FHIT gene in gall bladder cancer. METHODS: Five microsatellite markers D3S1217, D3S1300, D3S1313, D3S1600, and D3S2757, were selected. RESULTS: Among GBC cases the frequency of MSI-H and LOH was 17.5% and 27.5%, respectively. Significant difference was found between GBC and normal GB (p = .02), and GBC and CC groups (p= .002) when LOH was compared. CONCLUSIONS: Our results suggested CC might act as a preinvasive stage in the pathogenesis of GBC.

Is typing for HLA class II alleles beneficial in Indian children with idiopathic nephrotic syndrome?

This study was conducted to test the hypothesis that analysis of HLA class II type alleles will give important information on the prognosis of NS in children. We prospectively studied 100 consecutive children with idiopathic nephrotic syndrome and 202 controls belonging to the same geoethnic background. Typing for HLA Class II alleles at DR and DQ locus was carried out by using SSP (sequence specific oligonucleotides based method). In our study children were more likely to have nephrotic syndrome if the allele DQ-beta1*020X was present as compared to controls. On the other hand, DR-beta1*1001, DR-beta1*130X and DQ-beta1*030X were significantly lower among patients and likely to be protective. On analysing the different steroid response categories, we observed that the allele DQ-beta1*020X was significantly higher in infrequent relapsers (IFR) with a high etiological fraction of 0.714. Children were more likely to be steroid resistant if the allele DR-beta1*150X was present and the etiological fraction was high (0.754). The allele DQ-beta1*030X was significantly lower in steroid resistant patients (p=0.019, RR=0.1819, 95% CI=0.04430-0.7471) and likely to be protective. On analysing the haplotype distribution, we observed that occurrence of DR-beta1*070X-DQ-beta1*020X haplotype was significantly more common among patients with steroid sensitive nephrotic syndrome (23.94%) as compared to controls (12.5%) (p=0.01). In the steroid resistant group we observed that the haplotype DR-beta1*150X-DQ-beta1*060X was significantly more frequent as compared to steroid sensitive patients as well as controls p=0.01. We conclude that HLA typing in Indian children with NS helps to predict relapse frequency and steroid resistance.

Association of human leucocyte DR and DQ antigens in Crohn's disease in Asian Indians: a family study.

The pathogenesis of Crohn's disease (CD) involves an abnormal immune response to enteric bacteria in genetically susceptible individuals. There are no family studies regarding the association of CD with human leucocyte antigens (HLA) class II. In the present study, we have studied the association of HLA class II antigens in patients with CD and their first-degree relatives. Nine patients with CD and their first-degree relatives were studied. A group of 110 healthy unrelated and ethnically matched subjects were used as controls. Molecular HLA typing was done using the sequence-specific primer-based method. The transmission disequilibrium test (TDT) was used to analyze the results. A total of 65 individuals were included in the study; 52/56 first-degree relatives (92.8%) of 9 patients with CD consented to the study. The median age of patients was 40 years. When the distribution of the HLA class II antigens in patients was compared to that in controls no significant differences were observed even after applying the Yates correction. As the sample size of the population was small, the association of CD with DR and DQ alleles was further analyzed by using the TDT. Even after applying TDT, no significant association was observed. Familial aggregation of CD is uncommon in India. Crohn disease is not associated with HLA class II antigens in Indian patients. Genes of the major histocompatiblity complex are likely to contribute little to the susceptibility to Crohn disease in Indian patients.