A Broad Test Based on Fluorescent-Multiplex PCR for Noninvasive Prenatal Diagnosis of Cystic Fibrosis

Abstract

Background: Analysis of cell-free fetal DNA in maternal plasma is very promising for early diagnosis of monogenic diseases. However, it has been limited by the need to set up patient- or disease-specific custom-made approaches. Here we propose a universal test based on fluorescent multiplex PCR and size fragment analysis for an indirect diagnosis of cystic fibrosis (CF). Methods: The test, based on haplotyping, includes nine intra- and extragenic short tandem repeats of the CFTR locus, the coamplification of p.Phe508del (the most frequent mutation in CF patients worldwide), and a specific SRY sequence. The assay is able to determine the inherited paternal allele. Results: Our simple approach was successfully applied to 30 couples and provided clear results from the maternal plasma. The mean rate of informative markers was sufficient to propose it for use in indirect diagnosis. Conclusions: This noninvasive prenatal diagnosis test, focused on indirect diagnosis of CF, offers many advantages over current methods: it is simple, rapid, and cost-effective. It allows for the testing of a large number of couples with high risk of CF, whatever the familial mutation of the CFTR gene. It provides an alternative method to reduce the number of invasive tests.

Molecular Diagnosis and Genetic Counseling of Cystic Fibrosis and Related Disorders: New Challenges

“…Considerable progress has been made in the field of preimplantation genetic diagnosis [ 5 ] and non-invasive prenatal diagnosis. Early detection of paternal CF variants in maternal blood has been routinely available for a few years [ 6 , 26 ] and, in the very near future, non-invasive procedures should be available to all at-risk couples through NGS haplotype-based approaches [ 27 ].…”

Case report: Antenatal diagnostic of a polymalformative syndrome due to biallelic BRCA2 mutations

“…As described for CFTR variants, a similar approach could be considered for BRCA2 variants and proposed to this family. 8,12 Genetic counseling should allow the couple to decide whether to be informed of the result in case of a single BRCA2 muted allele in the fetus, since this would not result in any malformation, but would lead to a risk of cancer later in life. If only one parent is known to be a carrier of BRCA2 pathogenic mutation, diagnostic ultrasound should be offered.…”

“…As described for CFTR variants, a similar approach could be considered for BRCA2 variants and proposed to this family. 8 , 12 …”

The Role of Extended CFTR Gene Sequencing in Newborn Screening for Cystic Fibrosis

“…Reproductive attitudes would also inevitably change, as recently underlined [72]. Requests for prenatal diagnoses may increase, especially where non-invasive procedures have been recently available [73,74], but where a diagnosis of CF is made, with the growing availability of mutation-guided therapy the option of the continuation of pregnancy could be preferred over termination.…”