Methods for the diagnosis of fetal abnormalities
The present invention relates to methods for detecting, enriching, and analyzing rare cells that are present in the blood, e.g. fetal cells. The invention further features methods of analyzing rare cell(s) to determine the presence of an abnormality, disease or condition in a subject, e.g. a fetus by analyzing a cellular sample from the subject.
1. A method for determining the presence or absence of a fetal aneuploidy using a maternal blood sample, the method comprising:
a. obtaining a test sample comprising a mixture of fetal and maternal genomic nucleic acids from a maternal blood sample;
b. selectively amplifying a plurality of target nucleic acids from the test sample and a plurality of control nucleic acids from a plurality of control regions using primers labeled with a unique tag for each target nucleic acid and for each control nucleic acid, thereby generating amplification products, wherein the target nucleic acids are selected from one or more chromosomes to be tested for aneuploidy, and wherein the control regions are selected from regions of the genome where aneuploidy is not expected;
c. amplifying the amplification products using universal primers;
d. detecting the amplified target nucleic acids and amplified control nucleic acids;
e. quantifying the detected, amplified target nucleic acids and the detected, amplified control nucleic acids from the test sample;
f. analyzing the test sample for presence or absence of a fetal aneuploidy by comparing the quantity of the detected amplified target nucleic acids with the quantity of the detected amplified control nucleic acids; and
g. generating a report on presence or absence of aneuploidy in the maternal blood sample.
2. The method of claim 1 , wherein the target nucleic acids are selected from one or more of chromosomes X, Y, 13, 18, and 21.
3. The method of claim 1 , wherein the target nucleic acid sequences are quantified by chromatography, electrophoresis, comparative genomic hybridization (CGH), microarrays, or bead arrays.
4. The method of claim 3 , wherein the chromatography is selected from gas chromatography, supercritical fluid chromatography, and liquid chromatography.
5. The method of claim 3 , wherein the electrophoresis is selected from capillary electrophoresis, capillary zone electrophoresis, capillary isoelectric focusing, capillary electrochromatography, micellar electrokinetic capillary chromatography, isotachophoresis, transient isotachophoresis, and capillary gel electrophoresis.
6. The method of claim 1 , wherein the target nucleic acid sequences are quantified using molecular inversion probes (MIPs).
7. The method of claim 3 , wherein the target nucleic acid sequences are quantified using a microarray.
8. The method of claim 7 , wherein the microarray is used to detect at least 1,000 different target nucleic acids.
9. The method of claim 1 , wherein the chromosomes are tested for any one or more of fetal trisomy 13, trisomy 18, or trisomy 21.
10. The method of claim 1 , wherein the target nucleic acids are single nucleotide polymorphisms (SNPs), short tandem repeats (STRs), or RNA transcripts.
11. The method of claim 1 , wherein the amplification comprises:
hybridizing one set of oligonucleotides per target nucleic acid, wherein each set comprises two or more oligonucleotide probes that each hybridize to different regions within the target nucleic acid;
ligating the two or more hybridized oligonucleotide probes for each of the target nucleic acids to create amplification templates for each of the target nucleic acids; and
amplifying the amplification templates.
12. The method of claim 11 , further comprising attaching biotin to the target nucleic acids to generate biotin-labeled target nucleic acids.
13. The method of claim 12 , further comprising attaching the biotin-labeled target nucleic acids to a streptavidin coated solid support.
14. The method of claim 1 , wherein quantifying the target nucleic acids further comprises determining a gene or allele copy number or both a gene copy number and an allele copy number.
15. The method of claim 14 , further comprising determining fetal trisomy or monosomy based on the gene or allele copy number or the gene copy number and the allele copy number determination.
16. A method of determining the presence or absence of a fetal aneuploidy using a maternal blood sample, the method comprising:
a. obtaining a mixture of fetal and maternal genomic nucleic acids from a maternal blood sample;
b. hybridizing one set of oligonucleotide probes per target nucleic acid, wherein each set comprises two or more oligonucleotide probes that each hybridize to a target region within the target nucleic acid, and ligating the two or more hybridized oligonucleotide probes for each of the target nucleic acids to create amplification templates for each of the target nucleic acids, wherein each amplification template comprises a universal primer region coupled to a unique tag region;
c. amplifying the amplification templates using universal primers, thereby generating amplification products;
d. detecting the amplification products and quantifying the detected amplification products to determine a chromosomal copy number; and
e. generating a report on a presence or absence of aneuploidy in the maternal blood sample based on the chromosomal copy number.
17. The method of claim 16 , wherein the genomic nucleic acids are from one or more of chromosomes X, Y, 13, 18, or 21.
18. The method of claim 16 , wherein the fetal aneuploidy is a trisomy or a monosomy.
19. The method of claim 18 , wherein the trisomy is trisomy 13, trisomy 18, or trisomy 21.
20. The method of claim 16 , further comprising enriching the mixture of fetal and maternal genomic nucleic acids for fetal genomic nucleic acids.
21. The method of claim 16 , further comprising labeling the fetal and maternal genomic nucleic acids with biotin and immobilizing the biotin-labeled genomic nucleic acids to a solid support prior to step b.
22. The method of claim 21 , wherein the solid support comprises a streptavidin coating.
23. The method of claim 21 , wherein the solid support is a bead or particle.
24. The method of claim 16 , wherein detecting the amplification products and quantifying the detected amplification products is performed on a microarray.
25. The method of claim 24 , wherein the microarray is used to detect at least 1,000 different labeled nucleic acids.
26. The method of claim 16 , wherein detecting the amplification products and quantifying the detected amplification products is performed using molecular inversion probes (MIPs).
27. The method of claim 16 , wherein the amplification comprises one or more of quantitative polymerase chain reaction (Q-PCR), quantitative fluorescent PCR (QF-PCR), multiplex fluorescent PCR (MF-PCR), real time PCR (RT-PCR), single cell PCR, restriction fragment length polymorphism PCR (PCR-RFLP), PCR-RFLP/RT-PCR-RFLP, hot start PCR, nested PCR, in situ polonony PCR, in situ rolling circle amplification (RCA), bridge PCR, picotiter PCR and emulsion PCR, ligase chain reaction (LCR), transcription amplification, self-sustained sequence replication, selective amplification of target polynucleotide sequences, consensus sequence primed PCR (CP-PCR), arbitrarily primed PCR (AP-PCR), degenerate oligonucleotide-primed PCR (DOP-PCR) or nucleic acid based sequence amplification (NABSA).
28. The method of claim 27 , wherein the amplification comprises nested PCR.
29. The method of claim 27 , wherein the amplification comprises rolling circle amplification (RCA).
30. The method of claim 27 , wherein the amplification comprises bridge PCR.