77 results about "Trisomy" patented technology

The present methods are exemplified by a process in which maternal blood containing fetal DNA is diluted to a nominal value of approximately 0.5 genome equivalent of DNA per reaction sample. Digital PCR is then be used to detect aneuploidy, such as the trisomy that causes Down Syndrome. Since aneuploidies do not present a mutational change in sequence, and are merely a change in the number of chromosomes, it has not been possible to detect them in a fetus without resorting to invasive techniques such as amniocentesis or chorionic villi sampling. Digital amplification allows the detection of aneuploidy using massively parallel amplification and detection methods, examining, e.g., 10,000 genome equivalents.

Massively parallel sequencing of cell-free, maternal plasma DNA was recently demonstrated to be a safe and effective screening method for fetal chromosomal aneuploidies. Here, we report an improved sequencing method achieving significantly increased throughput and decreased cost by replacing laborious sequencing library preparation steps with PCR employing a single primer pair. Using this approach, samples containing as little as 4% trisomy 21 DNA could be readily distinguished from euploid samples.

Methods are disclosed for identifying chromosomal aneuploidy using heterozygous SNPs in a melting curve analysis. In one aspect, a panel of SNPs may be used. The heterozygous nature of the SNPs may in some aspects, act as an internal control for the melting curve analysis, and alleviate the need for external controls or competitors. In another aspect, each of the SNP in the panel may have a heterozygocity index of greater than about 30%. While a number of aneuploidies may be identified using the disclosed methods, in one aspect, the chromosomal aneuploidy identified may be trisomy 21.

Methods for prenatal screening for trisomy 21 employ examination of the fronto-maxillary facial (FMF) angle of a fetus. In one embodiment, the methods comprise obtaining a two or three dimensional image of a fetal face, measuring the FMF_bone angle on the image, and comparing the measured FMF_bone angle with an FMF_bone angle characteristic of chromosomally normal fetuses, wherein a measured FMF_bone angle greater than the FMF_bone angle characteristic of chromosomally normal fetuses provides an indication of an increased likelihood of the occurrence of trisomy 21 in the fetus. In another embodiment, the methods comprise obtaining a two or three dimensional image of a fetal face, measuring the FMF_skin angle on the image, and comparing the measured FMF_skin angle with an FMF_skin angle characteristic of chromosomally normal fetuses, wherein a measured FMF_skin angle greater than the FMF_skin angle characteristic of chromosomally normal fetuses provides an indication of an increased likelihood of the occurrence of trisomy 21 in the fetus. In additional embodiments, both FMF_bone angle and FMF_skin angle are measured and compared with values characteristic of chromosomally normal fetuses.

The invention relates to a kit used for screening the numerical abnormality of 21-trisomy and sex chromosome at early stage. The kit adopts quantitative fluorescence multiplex polymerase chain reaction technology, carries out the fluorescent primer sevenfold multiplex amplification respectively to differential genetic locus on the 21-trisomy and sex chromosome and analyzes the numerical abnormality of chromosome according to the difference of the dosage of amplified products, thus achieving the purpose of detecting the numerical abnormality of 21-trisomy and sex chromosome.

The invention relates to an amplification composition for detecting abnormal number of chromosomal aneuploid and a rapid detection kit, and belongs to the technical field of biology. The amplification composition can be used for amplification detection of STR sites related to 8 21# chromosomes, 6 18# chromosomes, 6 13# chromosomes and 3 X chromosomes and amplification detection of four amelo; all sites can be amplified by a quantitative fluorescent PCR (QF-PCR) technology, so as to detect the abnormal number of 21, 18, 13, X and Y chromosomal aneuploid. According to the kit, detection cycle is short, so the result can be obtained within 5 hours after obtaining the sample; the sensitivity is high; DNA at nanogram level, which is equal to DNA contained in 100 cells, is needed for each detection, so few samples are needed; 1 to 2ml of amniotic fluid can be collected to meet the demand; due to high sensitivity, a chimera containing more than 10% of trisomies can be detected.

The invention relates to preimplantation genetic diagnosis on an embryo by using new single cell nucleic acid amplification technology, which mainly utilizes the signal amplification action of the mRNA (messenger Ribose Nucleic Acid) to detect the multiplication or deletion of DNAs (Deoxyribonucleic Acids) of certain chromosome segments. According to the central dogma, the mRNA is transcribed by using the DNA as the template, the abnormity of the number of copies of the DNA template can cause the change of the quantity of the mRNAs; and in the transcription process, the multiplication or deletion of the DNA template can be amplified on the mRNA level, and can be easily detected. The main technical method is as follows: the single cell mRNA of a human embryo is subjected to PCR (Polymerase Chain Reaction) amplification after being subjected to reverse transcription and addition of a common primer; by using the amplification product as the template, quantitative PCR with a 96-pore plate is used for detecting the expression level of 8 genes of a single cell or a small amount of cells; and the detection result can be compared with a normal diploid embryo, so as to distinguish the embryo sex of X chromosome recessive inheritance family history, and the multiplication and deletion of Trisomy 21, Trisomy 18, Trisomy 13 and sex chromosome and carry out genetic diagnosis on some common chromosome anomalies.

The disclosure includes assays and methods for screening for risk of Down syndrome and/or trisomy 21 in a fetus. The assays and methods comprise determining the level of at least one biomarker selected from mucin 13 (MUC13), bile salt-activated lipase (CEL), dipeptidyl peptidase 4 (DPP4), carboxypeptidase A1 (CPA1), amyloid precursor protein (APP) and tenascin-C (TNC-C) polypeptides in a test biological sample from a pregnant subject, wherein a decreased level of MUC13, CEL, DPP4, and/or CPA1 polypeptide and/or an increased level of APP and/or TNC-C polypeptide in the test biological sample compared to a corresponding reference biomarker polypeptide level indicates an increased risk of Down syndrome or trisomy 21 in the fetus. The disclosure also includes assays, compositions, immunoassays, and kits for performing the methods disclosed herein.

The invention provides a kit for detecting genotype of human chromosome 21 STR (short tandem repeat). The kit comprises an amplification reagent and an amplification product detection reagent and mainly contains primers of 12 pairs of fluorescent markers, a molecular weight internal label containing the size of 14 fragments, an allele typing standard product and a quality control product. According to the kit disclosed by the invention, when the kit is used, the required quantity of specimens is small, the diagnosis is fast, and the kit is suitable for villi, amniotic fluid, blood and other tissues, and can be used for not only prenatal diagnosis, but also source analysis of extra chromosomes of a 21-trisomy aborted fetus; the kit can precisely diagnose the genotype and is conductive to presentation of diagnosis result and laboratory quality evaluation; and the kit can further realize fast, accurate, automatic and high-throughput detection of the number of chromosomes 21 and realize quality controllability and standardization of a detection result, and thus has clinical application prospects.

The invention relates to a quality control product, a preparation method thereof, a kit and a method for detecting trisomy 21 and 18 syndromes of fetuses. The digital PCR technology with single-molecule detection sensitivity and absolute quantitative capability is used, and a new simple and effective chromosome aneuploid non-invasive prenatal detection method is developed. By using peripheral blood of a pregnant woman, non-invasive prenatal detection can be completed on one sample within about 5 hours. By adopting the non-invasive prenatal detection technology based on the digital PCR, accurate, rapid and simple prenatal screening can be realized. The accuracy of the detection kit reaches 99%, the cost is only 1/5 that of the NIPT technology, and the detection time is 5 hours.

The present invention provides methods and assays for screening cells, such as stem cells, for chromosomal aberrations. In particular, the present invention provides a rapid, sensitive assay platform for detecting high and low levels of chromosomal aberrations present in a cell population. This includes, but is not limited to, detection of extra chromosomes (trisomies) as well as insertions of small segments that are undetectable using standard cytogenetic studies, wherein the abnormal cells comprise a low percentage of the total cell population.

The invention discloses a noninvasive prenatal screening 2, 1-trisomy syndrome kit, and relates to the technical field of a nucleic acid determination or inspection method. The noninvasive prenatal screening 2, 1-trisomy syndrome kit comprises a PCR reaction solution, wherein the PCR reaction solution contains a TaqMam UPL6-FAM probe and a TaqMam UPL15-TET probe, the TaqMam UPL6-FAM probe and the TaqMam UPL15-TET probe are respectively used for detecting No.18 and No.21 chromosomes, 20 pairs of primers are respectively designed for the No.21 and No.18 chromosomes, gene sequences of the primers are SEQ ID NO.1 to 40 and SEQ ID NO.41-80; and gene sequences of the TaqMam UPL6-FAM probe and the TaqMam UPL15-TET probe are SEQ ID NO.81 and SEQ ID NO.82. By adopting the noninvasive prenatal screening 2, 1-trisomy syndrome kit, the noninvasive prenatal screening of 21-trisomy syndrome, and the accuracy is high.