Three-hour analysis of non-invasive foetal sex determination: application of Plexor chemistry

Abstract

BackgroundThe knowledge of the individual genetic “status” in the prenatal era is particularly relevant in the case of positive family history for genetic diseases, in advanced maternal age and in the general screening for foetal abnormalities. In this context, here, we report an innovative molecular assay which utilizes the cell-free foetal DNA (cffDNA) as a source for the early and fast detection of the foetal sex. The study involved 132 pregnant women in their first 3 months of pregnancy, who agreed to give a blood sample. All the collected samples were immediately subjected to the separation of the plasma, which was utilized for the extraction of the cffDNA. Successively, the extracted cffDNA was analysed by a quantitative PCR (qPCR) method based on Plexor-HY chemistry, which is able to simultaneously identify, quantify and discriminate the autosomal DNA from the sex-linked DNA.ResultsOverall, the Plexor-HY assay demonstrated to be sensitive and specific for the determination of low-template DNA, such as the cffDNA. In fact, the Plexor-HY assay has been successfully performed in all the samples, identifying 70 males and 62 females. As the foetal sex can be provided in 120 min just by utilizing a maternal blood sample as cffDNA source, the assay represents a very fast, safe and non-invasive prenatal method.ConclusionsThe possibility of determining the foetal sex in the early prenatal life consents the application of our assay as a helpful screening test for subjects and families at risk of sex-linked disorders. Moreover, the early knowledge of the foetal sex may be of great help even for the specialist, who might promptly advise the patients concerning the foetal risk of inheriting sex-linked disorders and the clinical utility of performing an invasive prenatal diagnosis.Electronic supplementary materialThe online version of this article (doi:10.1186/s40246-016-0066-2) contains supplementary material, which is available to authorized users.

Identification of Duchenne/Becker muscular dystrophy mosaic carriers through a combined DNA/RNA analysis

“…In the first pregnancy of our case, the mutated fetal DMD genotype was detected on DNA purified from fetal cells obtained by amniocentesis. In consideration of the several research protocols available at the laboratory, this case appeared suitable for the application of the Plexor technology on cffDNA . In the second pregnancy, a noninvasive analysis has been conducted in order to define the fetal sex and plan the analytical process at the laboratory.…”

“…In consideration of the several research protocols available at the laboratory, [25][26][27] this case appeared suitable for the application of the Plexor technology on cffDNA. 21 In the second pregnancy, a noninvasive analysis has been conducted in order to define the fetal sex and plan the analytical process at the laboratory. The noninvasive analysis on cffDNA permitted to detect a male fetus.…”

“…In consideration of the detected mosaic status, on the subsequent pregnancy, the proposita plans to undergo further analyses. At 11 weeks of gestation, we determined the fetal sex through Plexor technology on cell‐free fetal DNA ( cffDNA ), according to protocols described elsewhere . Fetal DNA was then purified from chorionic villus sampling, and the familial DMD deletion was investigated.…”

“…At 11 weeks of gestation, we determined the fetal sex through Plexor technology on cell-free fetal DNA (cffDNA), according to protocols described elsewhere. 21 Fetal DNA was then purified from chorionic villus sampling, and the familial DMD deletion was investigated. Direct and segregation analyses (linkage) were performed in order to detect the familial DMD deletion.…”

Satisfaction with the gender of the baby and related factors

“…The gender of the fetus can be determined in the very early stages of pregnancy thanks to technology . Therefore, families may have a gender preference, which could lead to negative consequences .…”