OBJECTIVETo assess the value of quantitative fluorescence polymerase chain reaction (QF-PCR) for the detection of chromosomal aneuploidies in chorionic villus samples from early abortion.

METHODSOne hundred seventy seven specimens were collected. Genomic DNA was extracted, and aneuploidies of 8 chromosomes (13, 15, 16, 18, 21, 22, X and Y) were detected by QF-PCR analysis.

RESULTSThe QF-PCR was successful in 176 (99.4%) of the cases. All detection was completed in 48 hours. Sixty three(35.8%) cases have shown abnormal signals, which included 3 cases of trisomy 13, 3 cases of trisomy 15, 14 cases of trisomy 16, 2 cases of trisomy 18, 7 cases of trisomy 22, 3 cases of trisomy 21, 13 cases of 45,X, 1 case of 47,XXX, 2 cases of 47,XXY, 2 cases of haploidy, 11 cases of triploidy, 1 case of trisomy 16 and trisomy 22, 1 case of trisomy 21 and trisomy 22. Trisomy 16 was the most common chromosome aneuploidy (22.22%), which was followed by 45,X (20.63%), triploidy (17.46%) and trisomy 22 (11.11%).

CONCLUSIONQF-PCR is a quick and easy method for detecting chromosomal aneuploidies in chorionic villi tissue. The results can provide important information for genetic counseling for spontaneous abortions.

Abortion, Spontaneous ; diagnosis ; genetics ; Adult ; Aneuploidy ; Chorionic Villi ; chemistry ; Female ; Fluorescence ; Humans ; Pregnancy ; Prenatal Diagnosis ; Real-Time Polymerase Chain Reaction ; methods

OBJECTIVETo detect the methylation status of gastric cancer tissue genome by DNA methylation chip.

METHODSMethylation status of 6 samples of gastric cancer tissues and their matched adjacent tissues was analyzed using methylated DNA immunoprecipitation(MeDIP) combined with NibleGen chip. Significantly different methylated genes in promoter region and CpG island between two tissues were searched. Functions of these significantly different methylated genes were analyzed by Gene Ontology and Pathway assays.

RESULTSIn gene promoter regions, 113 significantly different methylated genes were identified in gastric cancer tissues, such as SHP1, FGF8 and CSF2RA, while 161 significantly different methylated genes were identified in their matched adjacent tissues, such as TNF, IGF2 and BMP7. In the CpG islands, 123 significantly different methylated genes were identified in gastric cancer tissues, such as WNT2B, JAK2 and TPT1, while 139 significantly different methylated genes were identified in their matched adjacent tissues, such as TNFRSF4, HOXC8 and NFYA. These genes located on different chromosomes. In gastric cancer tissues, the 1st and the 4th chromosomes had the most (both 11), the 18th and the 20th chromosomes had the least(both 1). In matched adjacent normal tissues, the 11th chromosome had the most (17), and no significantly different methylated gene was found on Y chromosome. These genes involved in many functions, such as protein phosphorylation, regulating cellular catabolism, ion transport, enzyme activity, transcriptional regulation, cell division, cell cycle regulation, and signal transduction.

CONCLUSIONSThere are significant differences between gastric cancer tissues and their matched adjacent tissues in DNA methylation. DNA methylation genes locate on different chromosomes, and their number and distribution vary widely. These genes may be associated with many pathways in carcinogenesis.