US 2003/0165852 A1 · Methods and reagents for identifying rare fetal cells in the maternal circulation

Abstract

This invention provides methods and compositions useful for identifying and diagnosing rare fetal cells in a mixed cell population such as a maternal blood sample. The methods entail the use of specific nucleic acid probes that hybridize to fetal cell associated RNAs to identify the rare fetal cells or antibodies that bind to polypeptides encoded by the fetal cell associated RNAs for fetal cell detection. The cells detected by the methods of the present invention are useful for diagnosing the fetal cells for a genetic trait of interest, such as trisomy 21. Novel methods for simultaneous screening for fetal cells and diagnosing the fetal cells are also provided. Compositions comprising the fetal cell associated nucleic acids of the invention and their encoded proteins are also provided. The present invention further provides kits useful for practicing the present methods.

Claims120

Dependent claims

A method for detecting a fetal cell in a maternal blood sample, comprising the steps of:

(a) contacting said maternal blood sample with a first probe, said first probe comprising:
(i) a nucleotide sequence corresponding to SEQ ID NO:
10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 40, 41 or 42,
(ii) a nucleotide sequence having at least 90% sequence identity to at least 20 consecutive nucleotides of SEQ ID NO:
10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 40, 41 or 42, or
(iii) a nucleotide sequence having at least 80% sequence identity to at least 40 consecutive nucleotides of SEQ ID NO:
10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 40, 41 or 42,
which first probe selectively or specifically hybridizes to mRNA in fetal cells if present in the maternal blood sample;
and
(b) identifying whether or not said maternal blood sample comprises a cell that comprises mRNA that detectably hybridizes to the first probe, thereby detecting whether or not said maternal blood sample contains a fetal cell.

7 more elements

A method for diagnosing an abnormality in a fetal cell, comprising the steps of:

(a) performing differential expression analysis on RNA or cDNA obtained from fetal liver myeloid cells relative to RNA or cDNA obtained from mature myeloid cells;
(b) identifying an RNA or cDNA species that is selectively or specifically expressed in the fetal liver myeloid cells, thereby identifying an RNA or cDNA species that is useful as a probe for fetal cells in the maternal circulation;
(c) contacting the maternal blood sample with a probe comprising a nucleotide sequence corresponding to all or a portion of the RNA or cDNA of step (b);
(d) identifying whether or not said maternal blood sample comprises a cell that comprises mRNA that detectably hybridizes to the first probe, thereby detecting whether or not said maternal blood sample contains a fetal cell;
and
(e) if the maternal blood sample contains a fetal cell, determining whether the abnormality exists in said fetal cell, thereby diagnosing the abnormality.

3 more elements

An isolated nucleic acid molecule selected from the group consisting of

(a) a nucleic acid molecule having a nucleotide sequence which is at least 90% identical to the nucleotide sequence of any of SEQ ID NOs:10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 40, 41 or 42, or a complement thereof;
(b) a nucleic acid molecule comprising at least 15 nucleotide residues and having a nucleotide sequence identical to at least 15 consecutive nucleotide residues of any of SEQ ID NOs:10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 40, 41 or 42, or a complement thereof,
(c) a nucleic acid molecule which encodes a polypeptide comprising the amino acid sequence of any of SEQ ID NOs:43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, or 78;
(d) a nucleic acid molecule which encodes a fragment at least 10 consecutive amino acid residues of a polypeptide comprising the amino acid sequence of any of SEQ ID NOs:43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, or 78;
(e) a nucleic acid molecule which encodes a fragment of a polypeptide comprising the amino acid sequence of any SEQ ID NOs:43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, or 78;
wherein the fragment comprises consecutive amino acid residues corresponding to at least half of the full length of any of said SEQ ID NOs;
and
(f) a nucleic acid molecule which encodes a naturally occurring allelic variant of a polypeptide comprising the amino acid sequence of any of SEQ ID NOs:43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, or 78, wherein the nucleic acid molecule hybridizes with a nucleic acid molecule consisting of the nucleotide sequence of any of SEQ ID NOs:10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 40, 41 or 42 under stringent conditions, or a complement thereof.

5 more elements

Dependencies are inferred from the claim text.

Methods and reagents for identifying rare fetal cells in the maternal circulation

Life of this patent

Methods and reagents for identifying rare fetal cells in the maternal circulation

Life of this patent

Abstract

Claims120