A novel approach to prenatal fetal sex diagnosis by detecting an insertion in the Y-chromosome of ovine Amelogenin gene

Abstract

It is completely clarified that both intact fetal cells and cell-free fetal nucleic acids cross the placenta and circulate in the maternal blood stream during pregnancy. In the current study we employed a new approach in applying Amelogenin gene for fetal sex prediction in ovine species. The amount of fetal DNA in the maternal blood was quantified using quantitative real-time PCR technique. Peripheral blood was obtained from 45 pregnant sheep with age of pregnancy varying from 8 to 18 weeks. Optimal primers were designed on Amelogenin intron 4, a Y specific insertion region in Amelogenin gene. For 42 (93.3%) ewes, agreement was verified between fetal sex prediction using cffDNA (cffDNA) and birth outcome. The test sensitivity, specificity and accuracy of fetal sex prediction were 96.5%, 87.5% and 93.3% respectively. The result of relative quantification showed that the cell-free fetal DNA values were significantly higher in ewes with more than 3 months of pregnancy relative to those with less than it. In conclusion, an insertion part in the ovine Y-chromosome Amelogenin gene could be successfully used for fetal sex prediction in ovine species using cell-free fetal DNA.