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

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

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.

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

OBJECTIVE: To investigate the polymorphism of 11 canine STR loci. METHODS: A fluorescent multiplex system with 11 STR loci (PEZ1, PEZ2, PEZ3, PEZ5, PEZ6, PEZ8, PEZ12, FH2010, FH2054, FH2132 and FH2611) was constructed independently and performed to amplify 105 samples from dogs. The character of these loci was analyzed with the PCR data. RESULTS: The distributions of genotypes and allele frequencies of 11 STR loci were obtained. The total power of discrimination for the 11 loci in canine population was 0.9999999 and the cumulative probability of exclusion was 0.9330621. The observed heterozygosity and polymorphism information content (PIC) were 0.502 and 0.640, respectively. CONCLUSION Each of the eleven canine STR loci has a high genetic polymorphism and can be applied for the parentage testing and individual identification. The fluorescent multiplex system is a reliable method in forensic application.
Alleles ; Animals ; Dogs/genetics* ; Forensic Genetics ; Gene Frequency ; Genotype ; Microsatellite Repeats/genetics* ; Polymorphism, Genetic

OBJECTIVE: To investigate the polymorphism of the TPH gene T3792A locus in Han ethnic group of north China and its application value in forensic science. METHODS: The polymorphism of T3792A locus of the TPH gene was analyzed by the ASPCR of blood samples from 173 unrelated individuals of north Chinese Han population. RESULTS: The distribution of the T3792A locus polymorphism of the TPH gene in Han ethnic group of north China followed the Hardy-Weinberg law, with the allele A and T gene frequency of 0.486 and 0.514, respectively. CONCLUSION The TPH gene T3792A locus shows a very good genetic polymorphism, and may be applied to individual identification and paternity testing.
Asian People/genetics* ; China/ethnology* ; Forensic Genetics ; Gene Frequency ; Humans ; Paternity ; Polymorphism, Genetic ; Tryptophan Hydroxylase/genetics*