马鞍山地区汉族人群15个STR基因座遗传多态性调查

目的:调查292名马鞍山地区汉族无关个体15个STR基因座的等位基因类型及其频率。方法:用硅珠法提取DNA,采用AmpFISTR Identifiler荧光标记复合扩增系统进行复合扩增;扩增产物用ABI3130xl型遗传分析仪检测,得到STR分型结果后统计15个基因座的基因频率。结果:15个STR基因座,累计个人识别率达0.999 999 999 999 999 985,累计非父排除率为0.999 998 96。结论:该系统在马鞍山地区汉族人群中具有高度多态性,适用于法医学亲权鉴定、个体识别以及DNA数据库的建立。     

Mini-STRs

The use of the short-tandem repeat (STR) as the DNA marker of choice in forensic profiling has lead to the construction of criminal intelligence databases that now contain millions of profiles used in the detection and linking of suspects and scenes. The incredible size and success rate of current systems have ensured that efforts to move away from STR profiling and toward the use of alternate DNA markers are practically impossible, mainly because of the financial implications involved in such a move. Problems are routinely encountered when template DNA is of suboptimal condition, as is commonly the case in the forensic laboratory, whereby full profile generation of degraded samples is not possible. A redesigned amplification protocol that results in the generation of shorter polymerase chain reaction products yet is fully compatible with current STR databases has been introduced: the MiniPlex.     

Statistical analysis of a large file of data from STIR profiles of British Caucasians to support forensic casework

Data from nearly 2500 British Caucasians, profiled using an STR quadruplex, have been analysed. The data came from several laboratories and represent samples from different geographical distributions. Analysis of the combined files shows that previous reports of failed independence tests were the results of sampling effects. A further convincing proof is given of the robustness of the statistical methods used to estimate evidential value in case-work. Comparisons between different samples show that regional effects between Scotland and the South of England have no importance from the forensic viewpoint.     

A Bayesian approach to validating STR multiplex databases for use in forensic casework

A previous paper in this journal has described the conventional statistical analysis of three databases (Caucasian, Afro-Caribbean and Asians from the Indian subcontinent) where individuals are typed at six short tandem repeat (STR) loci. This paper presents a Bayesian analysis of the same data and the approach is centred on the concept of estimating coancestry coefficients from mixed databases. Posterior distributions for the three databases are presented and discussed and the consequences of implementing bootstrap estimation procedures are also shown. Received: 18 November 1996 / Received in revised form: 21 April 1997     

F13B and CD4 allele frequencies in South West Switzerland

Allele frequencies of the two short tandem repeat (STR) systems F13B and CD4 were determined in a population sample from South West Switzerland using PCR analysis. We found five alleles for both STRs in a population sample of 205 unrelated individuals. No significant deviation from Hardy-Weinberg equilibrium was observed. Received: 14 October 1996 / Accepted in revised form: 6 January 1997     

F13B and CD4 allele frequencies in an Austrian population sample

Allele frequencies of the two short tandem repeat (STR) systems F13B and CD4 were determined in an Austrian population sample by PCR analysis. A total of 6 alleles for F13B and 8 alleles for CD4 could be observed in a population of 216 (F13B) and 198 (CD4) unrelated individuals. No significant deviations from Hardy-Weinberg equilibrium were observed.     

Identification of a base pair substitution at the tetranucleotide tandem repeat locus DHFRP2 (AAAC)n in a worldwide survey

An allele heterogeneity in a short tandem repeat at the human dihydrofolate reductase pseudogene (DHFRP2) was detected using non-denaturing gel electrophoresis and ethidium bromide staining. Sequence analysis of the allele, designated 9A, revealed the C to A substitution in the 8th AAAC repeat. A survey of 16 worldwide human populations showed that this mutation was spread through five continents at a relatively high frequency (up top = 0.19 in Europeans). Some statistical parameters of forensic interest were also calculated (h, PD, EC and PIC) for this polymorphism. This type of heterogeneity stresses the complexity of STR variation.     

Absence of chromosomal damage in the lymphocytes of patients treated with metronidazole for Trichomoniasis vaginalis

Chromosomal analysis was carried out on the peripheral lymphocytes of 12 patients receiving metronidazole 200 mg t.i.d. for 7 days for Trichomoniasis vaginalis infections. Samples were taken before, during and 3 weeks after completion of treatment, each patient thus acting as her own control. No increase in the chromosomal aberration frequency was found for any aberration type, either for the individual or for the group means. Thus metronidazole during short-term treatment was not found to exhibit any clastogenic effect on human lymphocytes in vivo.     

Brain distribution of genes related to changes in locomotor activity

The relationship between genes and behavior, and particularly the hyperactive behavior, is clearly not linear nor monotonic. To address this problem, a database of the locomotor behavior obtained from thousands of mutant mice has been previously retrieved from the literature. Data showed that the percent of genes in the genome related to locomotor hyperactivity is probably more than 1.56%. These genes do not belong to a single neurotransmitter system or biochemical pathway. Indeed, they are probably required for the correct development of a specific neuronal network necessary to decrease locomotor activity. The present paper analyzes the brain expression pattern of the genes whose deletion is accompanied by changes in locomotor behavior. Using literature data concerning knockout mice, 46 genes whose deletion was accompanied by increased locomotor behavior, 24 genes related to decreased locomotor behavior and 23 genes not involved in locomotor behavior (but important for other brain functions) have been identified.These three groups of genes belonged to overlapping neurotransmitter systems or cellular functions. Therefore, we postulated that a better predictor of the locomotor behavior resulting from gene deletion might be the brain expression pattern. To this aim we correlated the brain expression of the genes and the locomotor activity resulting from the deletion of the same genes, using two databases (Allen Brain Atlas and SymAtlas). The results showed that the deletion of genes with higher expression level in the brain had higher probability to be accompanied by increased behavioral activity. Moreover the genes that were accompanied by locomotor hyperactivity when deleted, were more expressed in the cerebral cortex, amygdala and hippocampus compared to the genes unrelated to locomotor activity. Therefore, the prediction of the behavioral effect of a gene should take into consideration its brain distribution. Moreover, data confirmed that genes highly expressed in the brain are more likely to induce hyperactivity when deleted. Finally, it is suggested that gene mutations linked to specific behavioral abnormalities (e.g. inattention) might probably be associated to hyperactivity if the same gene has elevated brain expression.     

增加7个STR基因位点在二联体亲子鉴定中的应用

目的在二联体亲子鉴定出现位点完全匹配但累积亲权指数（PI）较低的情况下,增加检测位点。方法选择STR_Typer₁0_v1荧光标记复合扩增试剂盒,对47例累计亲权指数较低的二联体亲子鉴定增加D11S2368,D13S325,D18S1364,D22-GATA198B05,D2S1772,D7S3048,D8S1132这7个位点的检测。结果通过增加7个STR基因位点的检测,有27例提高到99.974%以上,有14例增加到99.99%以上,增加STR检测没有观察到基因突变的现象。二联体检测的累计亲权指数有不同程度的增加,有8例从102以下提高到104以上。结论增加检测位点后二联体的检测结果更准确,结论更可靠,司法鉴定人的执业风险大大降低。