Patent ID: 7709194

Claim:
A method for detecting trisomy 18 in a fetus in a pregnant woman, comprising the steps of: (a) obtaining DNA in a blood sample from the woman after the 10th week of gestation; (b) amplifying at least a portion of the maspin gene from the fetus, wherein the portion of the maspin gene from the fetus and the portion from the woman are differentially methylated, thereby distinguishing the maspin gene from the woman and the maspin gene from the fetus in the blood sample; and (c) determining the levels of two alleles of a single nucleotide polymorphism in the maspin gene from the fetal DNA, wherein the fetus is heterozygous at the single nucleotide polymorphism in the maspin gene and determining the ratio of the alleles, wherein an increase or a decrease in the ratio of alleles from a standard control indicates the presence of trisomy 18 in the fetus.