Abstract:
The present invention is directed to methods of detecting nucleic acids in a biological sample. The method is based on a novel combination of a base extension reaction, which provides excellent analytical specificity, and a mass spectrometric analysis, which provides excellent specificity. The method can be used, for example, for diagnostic, prognostic and treatment purposes. The method allows accurate detection of nucleic acids that are present in very small amounts in a biological sample. For example, the method of the present invention is preferably used to detect fetal nucleic acid in a maternal blood sample; circulating tumor-specific nucleic acids in a blood, urine or stool sample; and donor-specific nucleic acids in transplant recipients. In another embodiment, one can detect viral, bacterial, fungal, or other foreign nucleic acids in a biological sample.
Abstract:
The present invention provides an efficient way for high throughput haplotype analysis. Several polymorphic nucleic add markers, such as SNPs, can be simultaneously and reliably determined through multiplex PCR of single nucleic acid molecules in several parallel single molecule dilutions and the consequent statistical analysis of the results from these parallel single molecule multiplex PCR reactions results in reliable determination of haplotypes present in the subject. The nucleic acid markers can be of any distance to each other on the chromosome. In addition, an approach wherein overlapping DNA markers are analyzed can be used to link smaller haplotypes into larger haplotypes. Consequently, the invention provides a powerful new tool for diagnostic haplotyping and identifying novel haplotypes.
Abstract:
The non-invasive detection of fetal chromosomal aneuploidies is demonstrated. Alleles of fetal RNA-SNPs present in a biological sample (e.g. maternal blood) containing fetal RNA are detected and quantified in order to determine the ratio of the alleles. This ratio is compared to a standard control consisting of euploid fetuses. Deviation of allele ratio indicates the presence of chromosomal aneuploidy.
Abstract:
The non-invasive detection of fetal chromosomal aneuploidies is demonstrated. Alleles of fetal RNA-SNPs present in a biological sample (e.g. maternal blood) containing fetal RNA are detected and quantified in order to determine the ratio of the alleles. This ratio is compared to a standard control consisting of euploid fetuses. Deviation of allele ratio indicates the presence of chromosomal aneuploidy.
Abstract:
The non-invasive detection of fetal chromosomal aneuploidies is demonstrated. Alleles of fetal RNA-SNPs present in a biological sample (e.g. maternal blood) containing fetal RNA are detected and quantified in order to determine the ratio of the alleles. This ratio is compared to a standard control consisting of euploid fetuses. Deviation of allele ratio indicates the presence of chromosomal aneuploidy.
Abstract:
Chromosomal abnormalities are responsible for a significant number of birth defects, including mental retardation. The present invention is related to methods for non-invasive and rapid, prenatal diagnosis of chromosomal abnormalities based on analysis of a maternal blood sample. The invention exploits the differences in DNA between the mother and fetus, for instance differences in their methylation states, as a means to enrich for fetal DNA in maternal plasma sample. The methods described herein can be used to detect chromosomal DNA deletions and duplications. In a preferred embodiment, the methods are used to diagnose chromosomal aneuploidy and related disorders, such as Down's and Turner's Syndrome.
Abstract:
The present invention is directed to a method for detecting and quantifying rare mutations in a nucleic acid sample. The nucleic acid molecules under investigation can be either DNA or RNA. The rare mutation can be any type of functional or non-functional nucleic acid change or mutation, such as deletion, insertion, translocation, inversion, one or more base substitution or polymorphism. Therefore, the methods of the present invention are useful in detection of rare mutations in, for example, diagnostic, prognostic and follow-up applications, when the targets are rare known nucleic acid variants mixed in with the wildtype or the more common nucleic acid variant(s).
Abstract:
This application describes the discovery that, in a pregnant woman, certain genes (such as RASSF1A, APC, CASP8, RARB, SCGB3A1, DAB2IP, PTPN6, THY1, TMEFF2, and PYCARD) originated from a fetus are highly methylated, whereas the same genes of maternal origin are unmethylated. This discovery allows the easy detection of one or more of these methylated fetal genes in a biological sample from a pregnant woman, serving as a universal indicator of the presence of fetal DNA in the sample. These fetal methylation markers are particularly useful as positive controls for a non-invasive analytical process during which the quality and quantity of fetal DNA are monitored. These newly identified fetal markers can also be measured directly for diagnosis of certain pregnancy-related conditions.
Abstract:
The present invention provides an efficient way for high throughput haplotype analysis. Several polymorphic nucleic acid markers, such as SNPs, can be simultaneously and reliably determined through multiplex PCR of single nucleic acid molecules in several parallel single molecule dilutions and the consequent statistical analysis of the results from these parallel single molecule multiplex PCR reactions results in reliable determination of haplotypes present in the subject. The nucleic acid markers can be of any distance to each other on the chromosome. In addition, an approach wherein overlapping DNA markers are analyzed can be used to link smaller haplotypes into larger haplotypes. Consequently, the invention provides a powerful new tool for diagnostic haplotyping and identifying novel haplotypes.
Abstract:
The present invention is directed to methods of detecting nucleic acids in a biological sample. The method is based on a novel combination of a base extension reaction, which provides excellent analytical specificity, and a mass spectrometric analysis, which provides excellent specificity. The method can be used, for example, for diagnostic, prognostic and treatment purposes. The method allows accurate detection of nucleic acids that are present in very small amounts in a biological sample. For example, the method of the present invention is preferably used to detect fetal nucleic acid in a maternal blood sample; circulating tumor-specific nucleic acids in a blood, urine or stool sample; and donor-specific nucleic acids in transplant recipients. In another embodiment, one can detect viral, bacterial, fungal, or other foreign nucleic acids in a biological sample.