Genetic polymorphisms of loci D18S53, D18S59, and D18S488 in fetuses from a Chinese Tianjin Han population

We investigated the genetic polymorphisms of three short tandem repeat (STR) loci, D18S53, D18S59, and D18S488, on chromosome 18 in fetuses from a Chinese Tianjin Han population. Sixty-four villus samples and 374 amniotic fluid samples were collected from fetuses. Quantitative fluorescence polymerase chain reaction was performed to amplify the STR loci, followed by scanned electrophoresis and quantitative analysis of the fluorescence signals. Hardy-Weinberg equilibrium (HWE) analysis was performed based on the genotype distributions of the STR loci to obtain the following population genetic data: genotype frequency, heterozygosity of observation (HO), polymorphism information content (PIC), probability of discrimination power (PD), and probability of exclusion (PE). We detected 15, 13, and 15 alleles of D18S53, D18S59, and D18S488, respectively. The genotype frequencies were found to be in line with HWE. The HO values of the three loci, D18S53, D18S59, and D18S488, were 0.797, 0.847, and 0.792; the PIC values were 0.81, 0.75, and 0.73; the PD values were 0.944, 0.901, and 0.881; and the PE values were 0.593, 0.689, and 0.585, respectively. D18S53, D18S59, and D18S488 loci are good genetic markers of chromosome 18, and show potential for use in the prenatal genetic diagnosis of Edwards' syndrome.

An in vivo model for the study of ovarian cancer and the persistence of characteristic mutations in xenografts

OBJECTIVE

To identify factors affecting xenograft growth of epithelial ovarian cancer (EOC) cells in nude mice and to detect characteristic mutations occurring in the xenografts following serial passage.

MATERIALS AND METHODS

A total of 64 human EOCs were subcutaneously inoculated in Balb/c nude mice in order to obtain a series of xenografts. Whole-exome sequencing was analyzed with Agilent SureSelect targeted enrichment capture system and Illumina Solexa Hiseq 2000 sequencing platform. Mutations were confirmed by comparison against the reference genome build 37.3.

RESULTS

The tumor take rate was 50% (32/64). TP53 mutation was detected in nine often Type II tumors. BRAF and CTNNB1 were not mutated in any of the samples, and PTEN mutation occurred in only one sample. The present data indicate that advanced stage serous EOCs and early stage non-serous EOCs were easy to grow in nude mice, and xenografts maintained the characteristic mutations.

CONCLUSIONS

Advanced stage serous EOCs and early stage non-serous EOCs were easy to grow in nude mice, and xenografts maintained the characteristic mutations. Xenografts in nude mice are useful in vivo models for the study of human EOCs.