Off-ladder Alleles Detected by Expressmarker22 Kit in Guangdong Han Population / 中山大学学报(医学科学版)

[Objective]To study the rare alleles frequencies and sequences of Expressmarker 22 kit in Guangdong Han Population.[Methods]3495 Samples from unrelated individuals in Guangdong Han Population were screened by using AGCU Expressmarker 22 kit(EX22)and ABI 3100 Genetic Analyzer. Then analyzed the frequencies of the off-ladder(OL)alleles and sequenced the rare alleles obtained based on comparison with the STRBase database and litera-ture.[Results]33 off-ladder alleles with 25 rare alleles were found in 10 STR loci,and allele frequencies ranged from 0.0003~0.0046. Sequencing of the11unreported rare OL alleles showed that most of them have incomplete repeats.[Conclusion]Off-ladder alleles especially the rare alleles are helpful to improve the power of discrimination and the power of exclusion and to provide samples which will be added its allele into ladders These OL-alleles will supplement forensic DNA database.

Genetic Polymorphisms of SNP Located in the 5' Region of VEGF Gene in Han Population in Guangdong / 法医学杂志

OBJECTIVES@#To investigate the genetic polymorphism of SNP located in the 5' region of the vascular endothelial growth factor （VEGF） gene in Han population in Guangdong and provide basic data for forensic application and population genetics research.@*METHODS@#The genetic polymorphisms of 4 SNP loci （rs699947, rs1570360, rs833061, rs2010963） within 5' region of VEGF gene of 184 unrelated individuals in Han population in Guangdong were analyzed by DNA micro sequencing technology SNaPshot. The statistical analysis was carried out by PowerMarker v3.25 software.@*RESULTS@#The genotype distributions of the 4 SNP loci within 5' region of VEGF gene of 184 unrelated individuals in Han population in Guangdong were in accordance with Hardy-Weinberg equilibrium （P>0.05） and 3 kinds of genotypes were detected from each loci. There was high linkage disequilibrium between the rs833061 and rs699947 SNP loci. Six haplotypes were observed, while the frequency of C-G-T-C, C-G-T-G, A-A-C-G and A-G-C-G were more than 10%, which were the main haplotypes. The discrimination probabilities （DP） of rs699947, rs833061, and rs2010963 loci were between 0.583 and 0.634, with the power of exclusion （PE） between 0.133 and 0.144. The DP and PE of haplotypes of 4 SNP were 0.868 and 0.438, respectively.@*CONCLUSIONS@#There are great polymorphisms in the 5' region of VEGF gene in Han population in Guangdong, which could be used as genetic indexes for individual identification and paternity testing, as well as association analysis of the related diseases.

SNP in Differentially Methylated Region Upstream of H19 Gene in Guangdong Han Population / 法医学杂志

OBJECTIVES@#To investigate the single nucleotide polymorphism （SNP） and haplotypes in differentially methylated region （DMR） upstream of H19 gene in Guangdong Han population.@*METHODS@#The PIA typing and restriction enzyme McrBC and HpaⅡ were used to digest the genomic DNA and obtain the individual uniparental DNA template strand. The data of uniparental SNP alleles, genotypes and haplotypes in DMR upstream of H19 gene were obtained by sequencing.@*RESULTS@#A total of 13 SNPs （rs10840167, rs2525883, rs12417375, rs4930101, rs2525882, rs2735970, rs2735971, rs11042170, rs2735972, rs10732516, rs2071094, rs2107425, and rs4930098） and one mutation locus （g7351c） were found. All loci followed the Hardy-Weinberg equilibrium （P>0.05） by statistical analysis. Except for rs12417375 （DP=0.279） locus, the DP of remaining 12 SNPs were 0.446-0.614, and the g7351c mutation locus （DP=0.013） was the particular loci of the Southern Chinese Han population. Eight haplotypes （designated as haplotype 1-8） were detected, in which 3 haplotypes had not yet been reported and the DP, PIC, PE and H were 0.891, 0.714, 0.524 and 0.758, respectively.@*CONCLUSIONS@#Obtained by PIA typing, the SNP in DMR upstream of H19 gene and its haplotypes genetic marker system have a high determination power and show a good practical value in forensic identification.

Analysis of de novo copy number variations in a family affected with autism spectrum disorders using high-resolution array-based comparative genomic hybridization / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To analyze de novo copy number variations (CNVs) in a Chinese family affected with autism spectrum disorders (ASD).</p><p><b>METHODS</b>Affymetrix Cytogenetics Whole Genome 2.7M Array assay was performed to identify potential CNVs in four members from the family.</p><p><b>RESULTS</b>A total of 89 de novo CNV regions were identified in the autistic siblings. The CNV regions in total have exceeded 1/1000 of the lengths of chromosomes 5, 11 and 14. In addition, de novo CNV regions were also identified at 3p26.1, 4q22.2, and 5p15.2, which encompassed 10 genes associated with nerve development including GRM7, GRID2 and CTNND2.</p><p><b>CONCLUSION</b>A number of nerve development associated genes were at the de novo CNV sites, which may provide new clues for genetic research of ASD. High-resolution array-comparative genomic hybridization is an effective method for detecting submicroscopic chromosomal imbalances.</p>

Establishment of an internal control for directed differentiation using pluripotent stem cell lines derived from heterozygotic twins / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To reprogram amniotic fluid cells into pluripotent stem cells in order to create an optimal internal control model for directed cell differentiation.</p><p><b>METHODS</b>Human amniotic fluid-derived cells (hAFDCs) from heterozygotic twin fetuses were induced by retroviral vectors encoding Oct4, Sox2, c-Myc and Klf4. In vivo pluripotency, differentiation capacity and karyotype of hAFDCs induced pluripotent stem cells (hAFDCs-iPSCs) were determined.</p><p><b>RESULTS</b>hAFDC-iPSCs derived from heterozygotic twins have maintained self renewal, with expression of high pluripotency marker gene detected at both mRNA and protein levels. The cells have maintained their differentiation capacity both in vitro and vivo, and showed normal karyotypes after long-term culturing in vitro.</p><p><b>CONCLUSION</b>hAFDCs-iPSCs derived from heterozygotic twins have good consistency in terms of genetic background, and can provide a good internal control for directed differentiation of iPSCs, and may be used an ideal source for autologous cell replacement therapy in the later life of the fetus.</p>