Polymorphism, Genetic ; Gene Frequency ; China ; Genetics, Population ; Microsatellite Repeats/genetics*

DNA pooling, a fast and economic study strategy, is widely used in areas of scientific research. In spite of various limits, researchers are making their efforts to improve DNA pooling toward a more perfect direction, including allele frequency detection and estimation of haplotypes. In haplotype estimation, more and more analyzing Methods originated from the expectation-maximization algorithm have appeared, with improved accuracy and practicality, such as HaploPool algorithm and PoooL algorithm.
Algorithms ; DNA ; genetics ; Gene Frequency ; genetics ; Gene Pool ; Genetic Variation ; genetics ; Genotyping Techniques ; Haplotypes ; genetics ; Humans

Tri-allelic pattern in autosomal STR is a common abnormal typing phenomenon in forensic DNA analysis, which brings difficulties and uncertainties to the evaluation of the evidence weight in actual cases. This paper reviews the types, formation mechanism, occurrence frequency, genetic pattern and quantitative evaluation of evidence of the tri-allelic pattern in autosomal STR in forensic DNA analysis. This paper mainly explains the formation mechanism and genetic patterns based on different types of tri-allelic pattern. This paper also discusses the determination of tri-allelic pattern and the quantitative method of evidence evaluation in paternity testing and individual identification. This paper aims to provide references for scientific and standardized analysis of this abnormal typing phenomenon in forensic DNA analysis.
Alleles ; DNA/genetics* ; Forensic Medicine ; Gene Frequency ; Microsatellite Repeats ; Humans

OBJECTIVES: To study the detection efficiency of trio full sibling with another known full sibling reference added under different number of autosomal STR typing systems. METHODS: Based on 43 detection systems consisting of 13 to 55 representative autosomal STR loci, 10 000 true families (full sibling group) and 10 000 false families (unrelated individual group) were randomly simulated. The full sibling index (FSI) was calculated based on the method of family reconstruction. The cumulative sibling relationship index (CFSI) of 0.000 1 and 10 000 were used as the evaluation thresholds, and the detection efficiency parameters were calculated and compared with the identification of the duo full sibling testing. RESULTS: With the increasing number of STR loci, the error rate and inability of judgement rate gradually decreased; the sensitivity, specificity, correct rate of judgment and other parameters gradually increased, and the system efficiency gradually improved. Under the same detection system, trio full sibling testing showed higher sensitivity, specificity, system efficiency and lower inability of judgement rate compared with duo full sibling testing. When the system efficiency was higher than 0.85 and inability of judgement rate was less than 0.01%, at least 20 STRs should be detected for trio full sibling testing, which was less than 29 STRs required by duo full sibling testing. CONCLUSIONS The detection efficiency of trio full sibling testing is superior to that of duo full sibling testing with the same detection system, which is an effective identification scheme for laboratories with inadequate detection systems or for materials with limited conditions.
Humans ; Siblings ; Microsatellite Repeats/genetics* ; DNA Fingerprinting ; Gene Frequency

OBJECTIVETo study the frequency distribution of flavin-containing monooxygenase 3 (FMO3) mutant alleles in 28 populations originating from 24 ethnic minorities in Yunnan of China.

METHODSFMO3 genotypes were analyzed by polymerase chain reaction-restriction fragment length polymorphism.

RESULTSThe average frequencies of FMO3/Stop(148), FMO3/Lys(158) and FMO3/Gly(308) were 0.395(0.174-0.803), 0.208 (0.056-0.414), 0.046(0-0.217), respectively. The frequencies of FMO3/Gly(308) in Blang, Huayaodai, Shuidai, Zhuang, De'ang, Jingpo, Nu and Hui populations were null.

CONCLUSIONIt was found that the frequencies of FMO3 mutant alleles varied not only in different ethnic groups, but also in different populations that stemmed from the same ethnic group.

Before a breeder invests selection pressure on a trait of interest, it needs to be established whether that trait is actually heritable. Some traits may not have been measured widely in pedigreed populations, for example, a disease or deformity may become more prevalent than previously, but is still relatively rare. One approach to detect inheritance would be to screen a commercial population to obtain a sample of "affecteds" (the test group) and to also obtain a random control group. These individuals are then genotyped with a set of genetic markers and the relationships between individuals within each group estimated. If the relatedness is higher in the test group than in the control group, this provides initial evidence for the trait being heritable. A power simulation shows that this approach is feasible with moderate resources.
Animals ; Breeding ; Gene Frequency ; Genetic Markers ; Heredity ; genetics ; Pedigree

Asian People/genetics* ; Gene Frequency ; Genetics, Population ; Humans ; Microsatellite Repeats/genetics* ; Phylogeny ; Polymorphism, Genetic/genetics*

Breast cancer is the leading cause of cancer death among women around the world and its incidence is annually increasing. The vitamin D receptor (VDR) gene is a member of the nuclear receptor superfamily, which is expressed in breast tissue and known to modulate the rate of cell proliferation. Association between the VDR gene polymorphisms and cancer development has been suggested by several studies. However, the relationship between VDR polymorphisms and breast cancer is controversial and has not been confirmed by all studies. The purpose of this study was to investigate the genotype frequencies and association of the VDR Bsm I and Taq I polymorphisms with breast cancer in Turkish patients. In this study, 78 patients with breast cancer and 27 healthy individuals were enrolled. The prevalence of the VDR Taq I and Bsm I alleles and the genotype frequencies in patients with breast cancer was similar to that in the normal population. Our data indicate that no significant differences exist between the patients and control subjects.
Breast Neoplasms/*genetics ; Gene Frequency ; Genotype ; Humans ; Polymerase Chain Reaction ; Polymorphism, Genetic/*genetics ; Receptors, Calcitriol/*genetics

The tetranucleotide repeat locus D7S809 was investigated in Cantonese population by polymerase chain reaction (PCR) amplification, subsequent polyacryramide gel electrophoresis and silver staining. 14 alleles and 50 genotypes were detected in 190 sample individuals. All alleles differed in size by 4 bp repeat. No interalleles were found. The heterozygosity, power of discrimination and chance of non-paternal exclusion were 0.8613, 0.9645 and 0.7184 respectively. No significant deviations from Hardy-Weinberg equilibrium were found. The D7S809 was a highly polymorphic, stable and accurate type locus and had been successfully applied to 100 paternity test cases.
Alleles ; Asian People/genetics* ; Gene Frequency ; Genetics, Population ; Genotype ; Humans ; Microsatellite Repeats/genetics* ; Paternity ; Polymorphism, Genetic

Objective To explore the genetic background and structure of Urumqi Mongolians, the previously developed 39-AIM-InDels panel for ancestry inference was utilized in the present study. Methods The blood samples of 145 unrelated healthy Urumqi Mongolian individuals were collected and genotyped. The compositions of ancestry information of Urumqi Mongolians were studied with 17 different populations from three continents （East Asia, Europe and Africa） as reference populations. Then, multiple population genetics and bioinformatics analysis methods were applied, the Fst and DA values between matched populations were compared and analyzed, PCA analysis was performed and a phylogenetic tree was constructed. The proportions of ancestry information components of Urumqi Mongolians were analyzed with Structure software, etc. Results The ancestry information components of Urumqi Mongolian group in different intercontinental populations accounted for 89%, 7%, and 3% of East Asian, European, and African populations, respectively. Compared with other intercontinental populations, Urumqi Mongolian group and East Asian populations have lower Fst and DA values, and they were in the same cluster in PCA analysis as well. In a phylogenetic tree, the Urumqi Mongolian group was in the same branch as East Asian populations. Conclusion Urumqi Mongolian group had relatively close genetic relationships with East Asian populations, and the proportion of its East Asian ancestry was about 89%.
Asian People/genetics* ; Forensic Genetics ; Gene Frequency ; Genetics, Population ; Humans ; INDEL Mutation ; Phylogeny ; Polymorphism, Single Nucleotide