A new stress model, a scream sound, alters learning and monoamine levels in rat brain

Most existing animal models for stress involve the simultaneous application of physical and psychological stress factors. In the current study, we described and used a novel psychological stress model (scream sound stress). To study the validity of it, we carried out acute and chronic scream sound stress. First, adult Sprague-Dawley (SD) rats were randomly divided into white noise, stress and background groups. The white noise group and stress group were treated with white noise and scream sound for 4h in the morning respectively. Compared with white noise and background groups, exposure to acute scream sound increased corticosterone (CORT) level and decreased latency in Morris water maze (MWM) test. The levels of noradrenaline (NE), dopamine (DA), 5-hydroxytryptamine (5-HT), 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA) and 5-hydroxyindoleacetic acid (5-HIAA) were altered in the striatum, hypothalamus and hippocampus of stress rats. Second, adult SD rats were randomly divided into background and stress groups, which were treated with scream sound for three weeks. Exposure to chronic scream sound suppressed body weight gain, increased corticosterone (CORT) level, influenced the morphology of adrenal gland, improved spleen and thymus indices, and decreased latency in MWM test. NE, DA, DOPAC, HVA and 5-HIAA levels were also altered in the brain of stress rats. Our results suggested that scream sound, as a novel stressor, facilitated learning ability, as well as altered monoamine levels in the rat brain. Moreover, scream sound is easy to apply and can be applied in more animals at the same time.

Dysregulation of miRNAs and their potential as biomarkers for the diagnosis of gastric cancer

Recent studies demonstrated that microRNA (miRNA) expression is dysregulated in numerous human cancers. In this study, we investigated the expression patterns of 8 miRNAs in gastric cancer and evaluated their clinical significance in order to identify potential biomarkers for gastric cancer diagnosis. Total RNA was extracted from gastric cancer and normal tissues from 20 pairs of paraffin-embedded specimens. The expression levels of the miRNAs were detected by quantitative reverse transcriptase polymerase chain reaction using specific stem-loop primers, with U6 as the internal reference gene. The association between miRNA expression level and clinicopathological factors was investigated. The expression of miR-21, -103, -106a, -221 and -222 in gastric cancer samples was significantly higher compared to that in the paired normal samples. Conversely, the expression of miR-143 and -195 in cancer tissues was significantly lower compared to that in normal tissues. However, miR-126 exhibited no difference between gastric cancer and normal tissues. A multivariate analysis demonstrated that the expression of miR-143 and -195 were associated with clinicopathological parameters, including depth of invasion and lymph node metastasis. This association may be applicable to future decisions regarding treatment or as a diagnostic biomarker.

A novel chronic stress-induced shift in the Th1 to Th2 response promotes colon cancer growth

Epidemiological data have shown that stress and other psychological factors might influence cancer onset and progression. However, to date, the mechanisms are not well understood. In the present study, we used chronic exposure to a scream as a novel form of sound stress to explore the influence of the chronic stress burden on colon cancer progression, and changes in the immune system were observed. Chronic exposure to scream sound stress induced freezing behavior in the mice and decreased the bodyweight gain. It also caused changes in the adrenal gland and increased serum corticosterone and norepinephrine levels. Cytokine microarray analysis showed changes in the levels of Th1 and Th2 cytokines. The chronic scream sound stress caused a shift from the Th1 to the Th2 response both in the circulation and in tumor-infiltrated lymphocytes, and it promoted colon cancer progression significantly. Taken together, chronic scream sound stress can be conveniently used as a novel chronic stress model. Chronic stress contributes to colon cancer progression and induces a Th1/Th2 imbalance in the mouse immune system, which is considered critical during cancer progression.

Cell proliferation in ependymal/subventricular zone and nNOS expression following focal cerebral ischemia in adult rats

Neuronal nitric oxide synthase (nNOS) regulates neurogenesis in normal developing brain, but the role of nNOS in neurogenesis in the ischemic brain remains unclear. To investigate the temporal and spatial relationship between cell proliferation of the ependymal/subventricular zone (SVZ), a principal neuroproliferative region in the adult brain, and nNOS expression, the male Sprague-Dawley rats weighing 250-350 g were used. The focal cerebral ischemia was induced by middle cerebral artery occlusion (MCAO). 10 microl of 0.2% fluorescence dye DiI was injected into the right lateral ventricle to prelabel ependymal/subventricular zone cells before ischemia. The rats were killed immediately after ischemia and days 1, 3, 7, 11, 14, 21 and 28 after ischemia. DiI-labeled cell counting was employed to assess cell proliferation. Immunohistochemistry and grayscale analysis were performed to determine nNOS localization and its quantity in the specific regions. Compared with control, the density of DiI-labeled cells in the ipsilateral ependyma/SVZ was significantly higher at days 1, 3, 7 and 11 after ischemia, whereas the quantity of nNOS expression in the ependyma/SVZ adjacent regions was significantly lower at the above time points. Additionally, nNOS positive cells were largely excluded from SVZ, and their long processes did not enter the ependyma/SVZ. Our results indicate that after focal cerebral ischemia, decreased nNOS expression in the ipsilateral ependymal/SVZ adjacent regions might be related to cell proliferation in the ependymal/SVZ.

Downregulation of miR-145 expression in oral squamous cell carcinomas and its clinical significance

BACKGROUND

MicroRNAs have been reported to play roles as oncogenes or tumor suppressor genes in human cancers. However, the expression levels of miR-145 in oral squamous cell carcinoma (OSCC) are unclear. The purpose of this study was to investigate the status of miR-145 expression in OSCC and determine its clinical significance.

PATIENTS AND METHODS

We examined miR-145 levels in 62 OSCC tissue samples and cell lines by quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR). The relationship between miR-145 expression and clinicopathologic factors of OSCC patients was analyzed.

RESULTS

The proportion of miR-145 low expression was 82.26% (51/62) among the 62 OSCC patients, and expression levels of miR-145 in OSCC tissue samples and cell lines were significantly lower than in non-tumor controls. miR-145 expression levels were not significantly associated with age (p = 0.607), sex (p = 0.213), location (p = 0.952), histology (p = 0.603), pT stage (p = 0.305), pTNM stage (p = 0.471), and lymphatic metastasis (p = 1.000).

CONCLUSION

miR-145 may be involved in the early tumorigenesis of oral squamous cells, and might be a potential biomarker in the early diagnosis of OSCC.

The decreased self-renewal potential of NPCs during human embryonic brain development with reduced activity of MAPKs

Study of neural progenitor cells (NPCs) is important for treatment of degerative diseases in central nervous system. One of the key questions in NPCs transplantation therapy is about the understanding of which stage of the NPCs in brain development is ideal. Herein we investigated survival, proliferation and apoptosis of NPCs from 12 w, 16 w and 20 w human embryonic brain, meanwhile, the phosphorylation of mitogen-activated protein kinases (MAPKs) signaling were analyzed. The results showed that the survival, proliferation and cell division of 16 w and 20 w human NPCs significantly decreased comparing with 12 w human NPCs in vitro; and the NPCs apoptosis remarkably increased. Phosphorylation of ERK1/2 of 16 w and 20 w NPCs significantly decreased comparing with 12 w human NPCs, however phosphorylation of p38 MAPK increased. NPCs proliferation increase when ERK1/2 signaling is activated by PMA. The results demonstrated that self-renewal potential of NPCs decreased in culture during human embryonic brain development, the activity of ERK signaling pathway were decreased, and suggest NPCs from 12-week fetuses might be better donor for cell transplantation during the period of 12-20 weeks because of their advantage on survival and proliferation.

[STAT1 and STAT2 participate in growth inhibition of human hepatoma HepG2 cells induced by phosphatidylethanolamine]

OBJECTIVE

To investigate the roles of STAT1 and STAT2 in growth inhibition induced by phosphatidylethanolamine (PE) in human hepatoma HepG2 cells.

METHODS

The growth of HepG2 cells exposed to 0.125, 0.25, 0.5 and 1.0 mmol/L PE was assessed by MTT assay, and the expressions of STAT1 and STAT2 were analyzed using immunocytochemical assay.

RESULTS

PE inhibited the growth of HepG2 cells in a dose-dependent manner and increased the expression of STAT1 and STAT2 in comparison with those in the control group. AG490, an inhibitor of JAKs, partially reversed PE-induced growth inhibition of HepG2 cells.

CONCLUSION

STAT1 and STAT2 are involved in the growth inhibition of human hepatoma HepG2 cells induced by PE.

STAT1/2 is involved in the inhibition of cell growth induced by U0126 in HeLa cells

The mitogen-activated protein kinase (MAPK) signaling cascade plays an important role in cell life. Herein we show that small interfering RNAs targeting MAPK1 can inhibit HeLa cell growth and induce apoptosis along with up-regulation of signal transducers and activator 1 and 2 (STAT1/2). However, across-talk between the ras-raf-ERK1/2 signalling cascade and the JAK-STAT pathway remain largely unknown. Using MEK inhibitor U0126 and JAK-2 inhibitor AG490, we analyzed the relationship between ERK1/2 and STAT1/2 in HeLa cells. U0126 inhibited HeLa cell growth, arrested the cell cycle at G1/G0, and induced cell apoptosis, and AG490 partially reversed the effects of U0126. U0126 induced up-regulation of ERK1/2 and down-regulation of phosphorylated ERK1/2, increased STAT1 and STAT2 expression in a dose-dependent manner, and activated STAT1/2 via their phosphorylation. AG490 markedly inhibited the phosphorylation of STAT1 and STAT2 and slightly increased that of ERK1/2 inhibited by U0126. We suggest that STAT1/2 is involved in the inhibition of cell growth induced by U0126 in HeLa cells.

HPV-16E6 can induce multiple site phosphorylation of p53

Modulation of the activity of tumor suppressor p53 is a key event in the replication of many viruses. They could manipulate p53 function through modification of phosphorylation for their own purpose. However, there are scarce data on the relationship between high risk human papillomavirus (HPV) E6 protein and p53 phosphorylation status. Therefore, we used a mammalian green fluorescence protein (GFP) expression system to express HPV-16E6 with GFP fusion proteins in wild-type p53 cell lines, 293T, MCF-7, and SMMC-7721 to trace the traffic and subcellular location of E6 protein. By immunoblotting, we determined the positive phosphorylated sites of p53 in the context of HPV-16E6. Using immunofluorescence techniques, we observed the distribution of phosphorylated p53 in all the cells we used. In conclusion, HPV-16E6 was predominantly located in nuclei of wild-type p53 cells, and it was able to induce phosphorylation of p53 at multiple sites, such as Ser15, Ser20, and Ser392. The level and time of these phosphorylated sites of p53 were different in HPV-16E6 expressing cells. Furthermore, the phosphorylated p53 was localized in the nuclei together with HPV-16E6.

In GFP with high risk HPV-18E6 fusion protein expressed 293T and MCF-7 cells, the endogenous wild-type p53 could be transiently phosphorylated at multiple sites

Background

Infected cells recognize viral replication as a DNA damage stress and elicit the host surveillance mechanism to anti-virus infection. Modulation of the activity of tumor suppressor p53 is a key event in the replication of many viruses. They could manipulate p53 function through phosphorylation modification for their own purpose. But there is rarely research about p53 phosphorylation status in the context of HPV-E6. Therefore, we investigated whether p53 could be phosphorylated by HPV-E6.

Methods

We used a mammalian green fluorescence protein (GFP) expression system to express HPV-18E6 with GFP fusion proteins (GFP-18E6) in wild-type (wt) p53 cell lines, such as 293T and MCF-7 cells to trace the traffic and subcellular location of E6 protein. By immunofluorescence technique and immunoblotting, we determined the positive phosphorylated sites of p53 and observed the distribution of phosphorylated p53 in the context of GFP-18E6.

Results

GFP-18E6 was predominantly located in nuclei of wt p53 cell lines, and it could induce transient phosphorylation of p53 at multiple sites, such as Ser¹⁵, Ser²⁰, and Ser³⁹². All the three sites of phosphorylated p53s were localized in nuclei together with GFP-18E6.

Conclusion

In GFP with high risk HPV-18E6 fusion protein expressed 293T and MCF-7 cells, the endogenous wt p53 could be transiently phosphorylated at multiple sites.

Retrovirus delivered neurotrophin-3 promotes survival, proliferation and neuronal differentiation of human fetal neural stem cells in vitro

Poor survival and insufficient neuronal differentiation are the main obstacles to neural stem cell (NSC) transplantation therapy. Genetic modification of NSCs with neurotrophins is considered a promising approach to overcome these difficulties. In this study, the effects on survival, proliferation and neuronal differentiation of human fetal NSCs (hfNSCs) were observed after infection by a neurotrophin-3 (NT-3) recombinant retrovirus. The hfNSCs, from 12-week human fetal brains formed neurospheres, expressed the stem cell marker nestin and differentiated into the three main cell types of the nervous system. NT-3 recombinant retrovirus (Retro-NT-3) infected hfNSCs efficiently expressed NT-3 gene for at least 8 weeks, presented an accelerated proliferation, and therefore produced an increased number of neurospheres and after differentiation in vitro, contained a higher percentage of neuronal cells. Eight weeks after infection, 37.9+/-4.2% of hfNSCs in the Retro-NT-3 infection group expressed the neuronal marker, this was significantly higher than the control and mock infection groups. NT-3 transduced hfNSCs also displayed longer protruding neurites compared with other groups. Combined these results demonstrate that NT-3 modification promote the survival/proliferation, neuronal differentiation and growth of neurites of hfNSCs in vitro. This study proposes recombinant retrovirus mediated NT-3 modification may provide a promising means to resolve the poor survival and insufficient neuronal differentiation of NSCs.

[Small interfering RNA-mediated nuclear factor-kappaB P65 suppression induces apoptosis of hepatic carcinoma SMMC-7721 cells]

OBJECTIVE

To study the mechanism of hepatic carcinoma cell apoptosis induced by small interfering RNA (siRNA)-mediated nuclear factor-kappaB (NF-kappaB) P65 silencing.

METHODS

Hepatic carcinoma SMMC-7721 cells were exposed to liposome-mediated transfection with NF-kappaB P65 siRNA synthesized by in vitro transcription, and the cells with empty liposome transfection and those without particular treatment served as the control groups. The expression of NF-kappaB P65 in the cells was detected by Western blotting, the cell viability examined by MTT assay, and the cell apoptosis assessed by flow cytometry. Immunohistochemistry was used to examine the expressions of Bcl-2 and Bax.

RESULTS

siRNA transfection significantly inhibited the expression of NF-kappaB P65 in SMMC-7721cells, with inhibition rates of 64.74% compared with the untreated cells and of 34.52% compared with the liposome-treated cells. The siRNA-treated SMMC-7721 cells also exhibited significant decrease in cell proliferation by 33.39% and 27.23% in comparison with the untreated and liposome-treated cells, respectively. NF-kappaB P65 siRNA induced obvious cell apoptosis with down-regulated Bcl-2 and up-regulated Bax expressions.

CONCLUSION

NF-kappaB p65 siRNA can induce SMMC-7721 cell apoptosis via the Bcl-2/Bax pathway.

Decreased neuronal nitric oxide synthase expression and cell migration in the peri-infarction after focal cerebral ischemia in rats

Neuronal nitric oxide synthase (nNOS) regulates neurogenesis in the normal developing brain, but the role of nNOS in neurogenesis of the adult ischemic brain remains unclear. The aim of this study was to investigate the temporal and spatial relationship between cell migration from the ependymal/subventricular zone (SVZ) to periinfarction and nNOS expression in the rat. Ependymal/subventricular zone cells were prelabeled with fluorescence dye DiI. Focal cerebral ischemia was induced by occlusion of the left middle cerebral artery. At 1, 3, 7, 14 and 21 days after ischemia, the rats were killed in order to determine the number of migrating cells, the colocalization of DiI and nNOS as well as nNOS quantity in specific regions. Compared to non-ischemic control and 1 day post-ischemia, the number of DiI-labeled cells in the selected regions increased at 3 days and peaked 14 days following ischemia. During 3-7 days post-ischemia, none of the migrating cells expressed nNOS and decreased nNOS expression was observed in the regions where migrating cells passed through. These results suggest the possible association between ependymal/SVZ cell migration and decreased nNOS expression within the areas including the migrating routes towards the peri-infarction.

Detection of CCND1 amplification using laser capture microdissection coupled with real-time polymerase chain reaction in human esophageal squamous cell carcinoma

Several methods have been used to detect CCND1 amplification or overexpression in esophageal squamous cell carcinoma (ESCC), but problems remain, associated with heterogeneity of tumor tissue and quantification of gene copies. Laser capture microdissection coupled with real-time polymerase chain reaction (PCR) is a reliable method for the molecular analysis of gene profiles in specific tissues. All 35 specimens of ESCC studied were paraffin-embedded, cut into tissue slides, and stained by hematoxylin-eosin. The pure ESCC cell and normal squamous epithelia populations were separated by LCM and then genomic DNA was extracted from the dissected cells. CCND1 amplification was detected with real-time FQ-PCR and with PCR. Amplification was calculated by the formula X = 2(-DeltaDeltaCt) and R = (CCND1/ACTB) CANCER/(CCND1/ACTB) NORMAL. Twenty (57%) of primary ESCC cancer cell groups had a detectable CCND1 amplification (range, 2.06-fold to 25.9-fold) with real-time FQ-PCR, but only 2 of 15 primary ESCC cancer cell groups had detectable CCND1 amplification by PCR. CCND1 amplification was not correlated with age, sex, size of tumor, histological grade, and lymph node metastasis. In conclusion, LCM coupled with real-time fluorescence quantitative-PCR technique is more precise than PCR for the identifying amplified oncogenes; The role of CCND1 amplification in ESCC development and progression needs more extensive study.

[A comparison study for differentiation between human fetal retinal progenitor cells and brain neural stem cells in vitro]

OBJECTIVE

Investigating the potential of differentiation of human fetal retinal progenitor cells (hRPCs) and brain neural stem cells (hBNSCs) in vitro.

METHODS

hRPCs and hBNSCs were isolated from human fetuses (8-12 weeks of gestation) and cultured in serum-free DMEM/F12 culture medium with N2 supplement, epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF) or culture medium with 10% fetal bovine serum (FBS) but without EGF and bFGF. Immunocytochemical and immunofluorescence studies were conducted for identification of neural stem cells, retinal progenitors or the subtypes of neurons, astrocytes, retinal ganglion cells and rod photoreceptors with the specific antibodies for Nestin, Pax6, Map2, GFAP, Thy-1 and Rhodopsin, respectively.

RESULTS

Both hRPCs and hBNSCs could proliferate and differentiate in DMEM/F12 + N2 with or without 10% FBS and expressed specific markers of immature neuroepithelial cells, retinal progenitors, mature neurons, astrocytes, retinal ganglion cells and rod photoreceptors. hBNSCs easily attached, spread out longer neurites and to form a network when cultured with serum contained medium. hRPCs were more difficult to attach and had only short dendrites.

CONCLUSIONS

Both hRPCs and hBNSCs can differentiate into retinal specific cell types in vitro. The adherent, migration and differential capacity of hRPCs and hBNSCs are different when these cells are induced by the serum-contained culture medium.

[Inhibition of the expression of p42MAPK in HeLa cell line by RNA interference]

OBJECTIVE

To screen for siRNAs that inhibit the expression of p42(MAPK) in HeLa cell line.

METHODS

Three p42(MAPK) siRNAs and one random siRNA were synthesized using Silencer siRNA Construction Kit, and labeled with Cy-3 for measurement of transfection effect. SiRNAs were transfected into HeLa cells by Lipofectamin 2000. The expression of p42(MAPK) was analyzed by Western blot. The biological effect of siRNAs on HeLa cell growth was monitored by MTT and flow cytometry.

RESULTS

Two siRNAs (siRNA-2 and siRNA-3) among three tested were identified to be able to downregulate the p42(MAPK) expression. A concurrent growth retardation of HeLa cell line was observed in comparison with the control.

CONCLUSION

Inhibition of p42(MAPK) expression with siRNA technique can inhibit the proliferation of HeLa cells.

[Small interfering RNA-mediated MAPK p42 silencing induces apoptosis of HeLa cells]

OBJECTIVE

To observe the effect of small interfering RNA (siRNA)-induced MAPK p42 silencing on the survival of HeLa cells.

METHODS

Two siRNAs targeting at the MAPK p42 gene and one random siRNA were synthesized respectively by Silencer siRNA Construction Kit and transfected into HeLa cells by Lipofectamin 2000. The expression of p42(MAPK) in the transfected HeLa cells was analyzed by Western blotting and immunohistochemistry, and the morphology of cells were observed with electron microscope. TUNEL assay and Annexin V/PI staining were employed for detecting the cell apoptosis.

RESULTS

The expression of p42(MAPK) in the HeLa cells was remarkably suppressed after transfection with the two siRNAs, reduced by about 2.5 and 3.2 folds respectively in comparison with the negative control. Chromatin margination in the cell nuclei were observed in the transfected cells, and TUNEL assay and Annexin V/PI staining further confirmed the occurrence of cell apoptosis.

CONCLUSION

In vitro MAPK p42 siRNA-1 and siRNA-2 transfection can specifically silence the gene expression and induce apoptosis of HeLa cells.

Ependymal/subventricular zone cells migrate to the peri-infarct region and differentiate into neurons and astrocytes after focal cerebral ischemia in adult rats

OBJECTIVE

To investigate the migration and differentiation of ependymal/subventricular zone cells after focal cerebral ischemia in rats, and reveal the origin of the newly generated neural cells in the peri-infarct region.

METHODS

Normal adult male Sprague Dawley rats weighing 250-350 g were used in this study. Before middle cerebral artery occlusion (MCAO), 10 microl of 0.2% DiI was injected into the lateral ventricle for prelabeling the ependymal/subventricular zone cells. After ischemia, cumulative BrdU labeling was employed to detect the newly generated cells and double immunofluorescent staining to identify cell differentiation. The labeled cells were observed with laser confocal microscopy.

RESULTS

In the non-ischemic control rats, DiI-labeled cells resided in the ependyma/subventricular zone. After focal cerebral ischemia, DiI-labeled cells were found in the corpus callosum, adjacent striatum and cortex, and some DiI/BrdU/glial fibrillary acidic protein (GFAP)-positive cells or DiI/BrdU/ neuronal nuclear antigen (NeuN)-positive cells were observed in the peri-infarct region in the striatum or cortex since day 14 after MCAO.

CONCLUSION

After focal cerebral ischemia, ependymal/subventricular zone cells migrate into the peri-infarct region where they differentiate into neurons and astrocytes. This finding may be important for understanding the source of adult neural stem cells and for developing new therapeutic intervention strategy through enhancing endogenous neurogenesis after brain injury.

A comparative genetic analysis between collagen-induced arthritis and pristane-induced arthritis

OBJECTIVE

To compare the genetic regulation of collagen-induced arthritis (CIA) with that of pristane-induced arthritis (PIA) in rats.

METHODS

A genome-wide linkage analysis of an (E3 x DA)DA backcross of rats with CIA (n = 364 male rats; the same strain combinations as previously used to determine the genetic control of PIA) was performed. The strongest loci in both CIA and PIA (i.e., Cia12/Pia4 and Cia13/Pia7) were isolated in congenic strains. Susceptibility in both congenic strains was tested in rats with CIA and in rats with PIA.

RESULTS

We found a striking, although not complete, similarity of the arthritis-controlling loci in CIA and in PIA, as well as the previously defined loci associated with cartilage destruction, antibody production, and the acute-phase response. All major PIA quantitative trait loci (QTLs) identified in early severe arthritis were also strong regulators of CIA. The 2 strongest QTLs, Cia12/Pia4 on chromosome 12 and Cia13/Pia7 on chromosome 4, were also analyzed in congenic strains with DA or E3 as the background genome. Consistent with the results of linkage analysis, the congenic strain experiments showed that the chromosome 4 locus was more penetrant in CIA than in PIA, while the chromosome 12 locus almost completely dominated the control of PIA severity.

CONCLUSION

The underlying genetic control of CIA was found to have many, but not all, pathogenic mechanisms in common with PIA, despite the use of a cartilage-specific antigen (type II collagen) to induce CIA but not PIA.

[Genetic polymorphism of 3 STR loci of CSF1PO, TPOX and TH01 in Chinese Sibo population]

OBJECTIVE

To obtain allele and genotype frequencies and related forensic data of CF1PO, TPOX and TH01 loci in Chinese Xinjiang Sibo population.

METHODS

Genomic DNA from peripheral blood mononuclear cells of normal Chinese Xinjing Sibo population was used as template, and CSF1PO, TPOX and TH01 fragments were amplified by PCR. The PCR products were analyzed by 4% denaturing PAGE and detected using silver stain detection.

RESULTS

Nine alleles were found at CSF1PO locus, eight alleles at TPOX locus and eight alleles at TH01 locus in Chinese Sibo population. All the 3 loci complied with Hardy-Weinberg equilibrium. The heterozygosities were 0.9426, 0.8361 and 0.8853, and the polymorphism information contents were 0.8298, 0.7213 and 0.7626 for CSF1PO, TPOX and TH01, respectively.

CONCLUSION

The data on the alleles frequency of these 3 STR loci might be used for individual identification and paternity identification and for genetic researches in Chinese Sibo population.

[Genetic polymorphism of D16S539, D7S820 and D13S317 loci in the Kazak ethnic population]

OBJECTIVE

To analyze the genetic polymorphism of D16S539, D7S820 and D13S317 in Chinese Kazak ethnic population from Xinjiang.

METHODS

One hundred and two unrelated individuals and a sample of families (n=42) were investigated by multiplex amplification, 6% denaturing PAGE and silver staining. And, the obtained allele frequencies were compared with those of other populations.

RESULTS

Eight, seven, eight alleles were observed at the 3 STR loci respectively and the genotypes distributions were in accordance with Hardy-Weinberg equilibrium. The expected heterozygosities for these loci were 0.9439, 0.9356 and 0.9304; the calculated polymorphism formation content (PIC) was 0.9905; the discrimination power (DP), 0.9998; the paternity exclusion (PE), 0.9572. In addition, significant difference was found in comparison with other populations, and in the sample of families (n=42) no new mutations could be found.

CONCLUSION

The multiplex examination of 3 STR loci can be used in forensic identification and population genetics research.