Abstract: The present invention relates to the identification of fetal specific nucleic acids and fetal cell markers in maternal plasma or serum. In particular, the present invention relates to methods which rely on the analysis of polymorphic alleles of a population to determine an allele which is possessed by the fetus but absent from the mother. Fetal specific alleles identified using the methods of the invention can be used to quantify fetal DNA from maternal plasma or serum. In addition, antigens encoded by alleles identified using the methods of the invention can be targeted in methods of isolating or detecting fetal cells.

Abstract: The present invention provides methods for identifying and/or enriching fetal cells from maternal blood, using as fetal cell markers the antibodies that the mother produces against paternally inherited fetal antigens. The fetal cell-maternal antibody complexes are identified and isolated using labelled agents that bind to the maternal antibodies. The present invention also provides fetal cells, isolated by use of said maternal antibodies, as a source of fetal DNA for prenatal genetic diagnosis of the fetus.