Colorectal cancer(CRC) is one of the most prevalent malignancies in the world. CRC-associated morbidity and mortality is continuously increasing, in part due to a lack of early detection. The existing screening tools ...Colorectal cancer(CRC) is one of the most prevalent malignancies in the world. CRC-associated morbidity and mortality is continuously increasing, in part due to a lack of early detection. The existing screening tools such as colonoscopy, are invasive and yet high cost, affecting the willingness of patients to participate in screening programs. In recent years, evidence is accumulating that the interaction of aberrant genetic and epigenetic modifications is the cornerstone for the CRC development and progression by alternating the function of tumor suppressor genes, DNA repair genes and oncogenes of colonic cells. Apart from the understanding of the underlying mechanism(s) of carcinogenesis, the aforementioned interaction has also allowed identification of clinical biomarkers, especially epigenetic, for the early detection and prognosis of cancer patients. One of the ways to detect these epigenetic biomarkers is the cell-free circulating DNA(circ DNA), a blood-based cancer diagnostic test, mainly focusing in the molecular alterations found in tumor cells, such as DNA mutations and DNA methylation.In this brief review, we epitomize the current knowledge on the research in circ DNA biomarkers-mainly focusing on DNA methylation-as potential blood-based tests for early detection of colorectal cancer and the challenges for validation and globally implementation of this emergent technology.展开更多
Non-invasive prenatal gene diagnosis has been developed rapidly in the recent years, and numerous medical researchers are focusing on it. Such techniques could not only achieve prenatal diagnosis accurately, but also ...Non-invasive prenatal gene diagnosis has been developed rapidly in the recent years, and numerous medical researchers are focusing on it. Such techniques could not only achieve prenatal diagnosis accurately, but also prevent tangential illness in fetuses and thus, reduce the incidence of diseases. Moreover, it is non-invasive prenatal gene diagnosis that prevents potential threaten and danger to both mothers and fetuses. Therefore, it is welcomed by clinical gynecologist and obstetrian, researchers of medical genetics, and especially, pregnancies. This review article touches briefly on the advanced development of using cell-free DNA, RNA in maternal plasma and urine for non-invasive prenatal gene diagnosis.展开更多
胎儿游离DNA(cell-free fetal DNA,cff-DNA)存在于孕妇妊娠期外周血中,其为携带胎儿相关遗传信息的DNA片段,可以进行胎儿染色体、基因相关疾病筛查。因其操作风险低、无副作用,目前已被广泛用于无创产前诊断检测(non-invasive prenatal ...胎儿游离DNA(cell-free fetal DNA,cff-DNA)存在于孕妇妊娠期外周血中,其为携带胎儿相关遗传信息的DNA片段,可以进行胎儿染色体、基因相关疾病筛查。因其操作风险低、无副作用,目前已被广泛用于无创产前诊断检测(non-invasive prenatal testing,NIPT)。无创cff-DNA血型检测是运用分子生物学检测cff-DNA血型相关基因,得出胎儿血型结果。以此在妊娠期即可检测出胎母血型是否一致,判断胎儿有无发生血型不合所致胎儿新生儿溶血病(hemolytic disease of the fetus and newborn,HDFN)的风险。展开更多
本研究针对不同妊娠时期细毛羊进行胎儿性别鉴定工作。首先对外周血浆/血清分别采用加热法和酚-氯仿法提取游离DNA。通过普通PCR扩增雄性性别决定基因(sex determining region Y,SRY)和β-actin检测基因的目的片段。鉴于部分样品未扩增...本研究针对不同妊娠时期细毛羊进行胎儿性别鉴定工作。首先对外周血浆/血清分别采用加热法和酚-氯仿法提取游离DNA。通过普通PCR扩增雄性性别决定基因(sex determining region Y,SRY)和β-actin检测基因的目的片段。鉴于部分样品未扩增出SRY基因目的片段,设计2对内外引物,运用优化后的巢式PCR体系再次针对SRY目的基因展开特异性扩增。最后对每个妊娠时间段的鉴定结果和实际生产结果进行统计,计算准确率。结果表明:加热法和酚-氯仿法均成功分离提取出妊娠母羊外周血浆/血清中的游离DNA,并扩增出β-actin检测基因片段;SRY阳性样本扩增出了SRY目的基因片段和β-actin检测基因片段,SRY阴性样本只扩增出了β-actin检测基因片段;性别鉴定的平均准确率达到81.25%(19.5/24),SRY基因检出率与妊娠时间的长短呈正比。结论,本研究建立了一种基于外周血游离DNA检测细毛羊胎儿性别的非创伤性且高效低廉的产前诊断技术,但性别鉴定的准确率还有待提高。展开更多
文摘Colorectal cancer(CRC) is one of the most prevalent malignancies in the world. CRC-associated morbidity and mortality is continuously increasing, in part due to a lack of early detection. The existing screening tools such as colonoscopy, are invasive and yet high cost, affecting the willingness of patients to participate in screening programs. In recent years, evidence is accumulating that the interaction of aberrant genetic and epigenetic modifications is the cornerstone for the CRC development and progression by alternating the function of tumor suppressor genes, DNA repair genes and oncogenes of colonic cells. Apart from the understanding of the underlying mechanism(s) of carcinogenesis, the aforementioned interaction has also allowed identification of clinical biomarkers, especially epigenetic, for the early detection and prognosis of cancer patients. One of the ways to detect these epigenetic biomarkers is the cell-free circulating DNA(circ DNA), a blood-based cancer diagnostic test, mainly focusing in the molecular alterations found in tumor cells, such as DNA mutations and DNA methylation.In this brief review, we epitomize the current knowledge on the research in circ DNA biomarkers-mainly focusing on DNA methylation-as potential blood-based tests for early detection of colorectal cancer and the challenges for validation and globally implementation of this emergent technology.
文摘Non-invasive prenatal gene diagnosis has been developed rapidly in the recent years, and numerous medical researchers are focusing on it. Such techniques could not only achieve prenatal diagnosis accurately, but also prevent tangential illness in fetuses and thus, reduce the incidence of diseases. Moreover, it is non-invasive prenatal gene diagnosis that prevents potential threaten and danger to both mothers and fetuses. Therefore, it is welcomed by clinical gynecologist and obstetrian, researchers of medical genetics, and especially, pregnancies. This review article touches briefly on the advanced development of using cell-free DNA, RNA in maternal plasma and urine for non-invasive prenatal gene diagnosis.
文摘胎儿游离DNA(cell-free fetal DNA,cff-DNA)存在于孕妇妊娠期外周血中,其为携带胎儿相关遗传信息的DNA片段,可以进行胎儿染色体、基因相关疾病筛查。因其操作风险低、无副作用,目前已被广泛用于无创产前诊断检测(non-invasive prenatal testing,NIPT)。无创cff-DNA血型检测是运用分子生物学检测cff-DNA血型相关基因,得出胎儿血型结果。以此在妊娠期即可检测出胎母血型是否一致,判断胎儿有无发生血型不合所致胎儿新生儿溶血病(hemolytic disease of the fetus and newborn,HDFN)的风险。
文摘本研究针对不同妊娠时期细毛羊进行胎儿性别鉴定工作。首先对外周血浆/血清分别采用加热法和酚-氯仿法提取游离DNA。通过普通PCR扩增雄性性别决定基因(sex determining region Y,SRY)和β-actin检测基因的目的片段。鉴于部分样品未扩增出SRY基因目的片段,设计2对内外引物,运用优化后的巢式PCR体系再次针对SRY目的基因展开特异性扩增。最后对每个妊娠时间段的鉴定结果和实际生产结果进行统计,计算准确率。结果表明:加热法和酚-氯仿法均成功分离提取出妊娠母羊外周血浆/血清中的游离DNA,并扩增出β-actin检测基因片段;SRY阳性样本扩增出了SRY目的基因片段和β-actin检测基因片段,SRY阴性样本只扩增出了β-actin检测基因片段;性别鉴定的平均准确率达到81.25%(19.5/24),SRY基因检出率与妊娠时间的长短呈正比。结论,本研究建立了一种基于外周血游离DNA检测细毛羊胎儿性别的非创伤性且高效低廉的产前诊断技术,但性别鉴定的准确率还有待提高。
