Chromosome Y as a marker for sex discrepancies in patients with organ transplants: a case report

[Towards a generalization of non-invasive prenatal diagnosis of single-gene disorders? Assesment and outlook]

OBJECTIVES

The screening of fetal aneuploidies and non-invasive prenatal diagnosis of monogenic diseases (NIPD-MD) both rely on the study of free fetal DNA in maternal circulation, but their respective rise was unequal. Development of NIPD-MD has taken longer as it represents a less attractive commercial dynamic for industry, but also because it usually involves the development of tailored tests specific to each pathogenic variant.

METHODS

We have carried out a review of the literature on the various indications and technologies involved in the use of NIPD-MM. We present its current implementation and its development in France.

RESULTS

To date, NIPD-MD has been routinely offered in France for several years by the laboratories of the French NIPD-MD network but remains mostly limited to the exclusion of paternal or de novo variants, the exclusion DPNI-MD. Indeed, it is still difficult to study the transmission of maternal variants from circulating free DNA analysis, due to its biological complexity: coexistence and predominance of similar DNA sequences of maternal origin. Different strategies, either direct or indirect, are being evaluated to establish fetal status regardless of the parental origin of the disease or its transmission mode. The emergence of commercial screening solutions for monogenic diseases complements the arsenal of prenatal exploration tools for these diseases.

CONCLUSION

The multitude of existing technologies and protocols may complicate the information provided during antenatal consultations, but mastery of know-how and knowledge of ethical issues of NIPD-MD will ensure optimal service and better management of pregnancies at risk of transmitting monogenic disease.

Genetic Screening and Teratogenic Exposures: Considerations in Caring for the Uterus Transplant Patient

Counseling the uterus transplant patient requires an enhanced knowledge of unique genetic challenges that include an understanding of the spectrum of Mayer-Rokitansky-Küster-Hauser syndrome. Patients should understand their options for genetic screening and testing including preimplantation genetic testing for aneuploidy, genetic screening, and diagnostic testing. This patient population is potentially at risk for fetal anomalies due to the increased susceptibility to infections, such as cytomegalovirus. There are management strategies to minimize this risk. The risk of teratogenicity from mycophenolate is eliminated by a washout period before embryo transfer.