Publications by authors named "Francoise Charbonnier"

Background: Li-Fraumeni syndrome (LFS) predisposes individuals to a wide range of cancers from childhood onwards, underscoring the crucial need for accurate interpretation of germline variants for optimal clinical management of patients and families. Several unclassified variants, particularly those potentially affecting splicing, require specialised testing. One such example is the NM_000546.

View Article and Find Full Text PDF

While de novo variants (DNV) are overall at low risk of recurrence in subsequent pregnancies, a subset is at high risk due to parental mosaicism. Accurately identifying cases of parental mosaicism is therefore important for genetic counseling in clinical care. Some studies have investigated the rate of parental mosaics, but most were either limited by the sensitivity of the techniques (i.

View Article and Find Full Text PDF

Background: Reverse transcription-quantitative PCR on nasopharyngeal swabs is currently the reference COVID-19 diagnosis method but exhibits imperfect sensitivity.

Methods: We developed a multiplex reverse transcription-digital droplet PCR (RT-ddPCR) assay, targeting 6 SARS-CoV-2 genomic regions, and evaluated it on nasopharyngeal swabs and saliva samples collected from 130 COVID-19 positive or negative ambulatory individuals, who presented symptoms suggestive of mild or moderate SARS-CoV2 infection.

Results: For the nasopharyngeal swab samples, the results obtained using the 6-plex RT-ddPCR and RT-qPCR assays were all concordant.

View Article and Find Full Text PDF
Article Synopsis
  • The study focuses on interpreting germline variants in cancer patients to improve medical management, especially as the number of tests increases.
  • Researchers developed a functional assay using patients' blood to assess p53 functionality after exposure to doxorubicin, measuring its impact through specific mRNA and transcriptional responses.
  • Results showed significant differences in p53 scores between wild-type individuals and those with pathogenic variants, highlighting the assay's potential for rapid classification of variants and identifying non-coding functional variants.
View Article and Find Full Text PDF
Article Synopsis
  • * The results showed a high positive predictive value (PPV) of 87.8% from gene panel data and 86.4% from whole-exome sequencing, with perfect sensitivity and specificity for a subset of gene comparisons.
  • * The findings suggest that adopting an NGS-only approach could be more cost-effective and provide stable diagnostic yields, with the CANOES workflow enabling detection of CNVs at a detailed exon level that may be missed by other methods.
View Article and Find Full Text PDF

Background: Recent advances in the field of congenital heart disease (CHD) have significantly improved the overall prognosis. Now more attention is being given to health-related quality of life (HRQoL) and promotion of physical activity. Non-invasive relaxation therapy may be effective in cardiac patients concerned with exercise-induced dyspnoea.

View Article and Find Full Text PDF
Article Synopsis
  • A massive parallel sequencing approach has been developed for diagnosing inherited colorectal cancer (CRC) by quickly capturing and analyzing specific genetic sequences in 10 key genes linked to Mendelian CRC.
  • The sequencing was performed using advanced Illumina platforms and involved a comprehensive bioinformatics pipeline for precise mapping, variant calling, and structural variant detection.
  • The analysis of 1644 cases revealed a 20% detection rate of harmful genetic variants, which increased to 37% for Lynch syndrome patients, highlighting the method's effectiveness in identifying complex genetic alterations related to CRC.
View Article and Find Full Text PDF

Background: Asthma is the most common chronic disease in pediatrics. Along with the usual drug therapy using corticosteroids and bronchodilators, some interest has been shown for adjuvant therapies, such as sophrology. However, the level of evidence for non-pharmaceutical therapies in asthma remains low, especially in children.

View Article and Find Full Text PDF

Purposes: Hydrops fetalis is a life-threatening fetal condition, and 85% of all cases are classified as nonimmune hydrops fetalis (NIHF). Up to 15% of NIHF cases may be due to inborn errors of metabolism (IEM), but a large proportion of cases linked to metabolic disorders remains undiagnosed. This lack of diagnosis may be related to the limitations of conventional biological procedures, which involve sequential investigations and require multiple samples and steps.

View Article and Find Full Text PDF
Article Synopsis
  • Development of certain tumors before age 31 or multiple cancers may indicate germline mutations, which are significant in the context of Li-Fraumeni syndrome (LFS).
  • This study analyzed 328 patients with germline mutations, finding that 14% of cases involved de novo mutations, with some occurring during embryonic development.
  • The researchers also discovered mosaic mutations in both affected individuals and their unaffected relatives, emphasizing the need for medical labs to effectively identify these mutations during testing.
View Article and Find Full Text PDF
Article Synopsis
  • * A family study revealed a specific stop mutation in the EXT2 gene associated with isolated chondrosarcomas, primarily in the ribs, regardless of traditional signs of multiple osteochondromas on imaging.
  • * This finding suggests that EXT2 mutations should be considered when evaluating patients for inherited chondrosarcoma risk, even if they don't show typical symptoms of multiple osteochondromas.
View Article and Find Full Text PDF

Intratumor genetic heterogeneity underlies the ability of tumors to evolve and adapt to different environmental conditions. Using CRISPR/Cas9 technology and specific DNA barcodes, we devised a strategy to recapitulate and trace the emergence of subpopulations of cancer cells containing a mutation of interest. We used this approach to model different mechanisms of lung cancer cell resistance to EGFR inhibitors and to assess effects of combined drug therapies.

View Article and Find Full Text PDF

We describe the case of a young patient with calcifying encephalopathy, born to asymptomatic parents. An extensive hypothesis-driven etiological assessment was performed and failed to detect the precise etiology during many years. We therefore decided to perform whole exome sequencing of the child-unaffected parents trio.

View Article and Find Full Text PDF

To determine if the at-risk single-nucleotide polymorphism (SNP) alleles for colorectal cancer (CRC) could contribute to clinical situations suggestive of an increased genetic risk for CRC, we performed a prospective national case-control study based on highly selected patients (CRC in two first-degree relatives, one before 61 years of age; or CRC diagnosed before 51 years of age; or multiple primary CRCs, the first before 61 years of age; exclusion of Lynch syndrome and polyposes) and controls without personal or familial history of CRC. SNPs were genotyped using SNaPshot, and statistical analyses were performed using Pearson's χ(2) test, Cochran-Armitage test of trend and logistic regression. We included 1029 patients and 350 controls.

View Article and Find Full Text PDF

To identify novel genetic bases of early-onset epithelial ovarian tumors, we used the trio exome sequencing strategy in a patient without familial history of cancer who presented metastatic serous ovarian adenocarcinomas at 21 years of age. We identified a single de novo mutation (c.1157A>G/p.

View Article and Find Full Text PDF

Several studies have reported that, in Lynch syndrome resulting from mutations of the mismatch repair (MMR) genes, a CA repeat ≤17 within the IGF1 promoter, SNPs within the xenobiotic metabolizing enzyme gene CYP1A1 and SNPs on 8q23.3 and 11q23.1 modify colorectal cancer (CRC) risk in MMR mutation carriers.

View Article and Find Full Text PDF

Objective: No validated biologic prognostic marker is presently available in metastatic colorectal cancer (MCRC). We prospectively evaluated the prognostic value of circulating mutant DNA in 31 patients presenting an unresectable MCRC treated by chemotherapy, and we used, as tumor markers, KRAS mutations and methylation of the RASSF2A promoter.

Methods: Detection in the serum of KRAS mutation and RASSF2A methylation were performed using sensitive methods, respectively, real-time polymerase chain reaction (PCR) performed in the presence of a peptide nucleic acid specific of the wild-type sequence and methyl-specific PCR after bisulfite treatment.

View Article and Find Full Text PDF

Numerous unclassified variants (UVs) have been found in the mismatch repair genes MLH1 and MSH2 involved in hereditary nonpolyposis colorectal cancer (HNPCC or Lynch syndrome). Some of these variants may have an effect on pre-mRNA splicing, either by altering degenerate positions of splice site sequences or by affecting intronic or exonic splicing regulatory sequences such as exonic splicing enhancers (ESEs). In order to determine the consequences of UVs on splicing, we used a functional assay of exon inclusion.

View Article and Find Full Text PDF

Splenomegaly with sea-blue histiocytes, thrombocytopenia and hypertriglyceridemia is a very rare association that has been described in only one report to date. The molecular defect in the two reported patients consists in a deletion of a leucine at position 149 in the receptor-binding region of the apoE molecule. Here, we report on another family in whom the proband and his brother were diagnosed with splenomegaly, thrombocytopenia and hypertriglyceridemia.

View Article and Find Full Text PDF

MSH2 rearrangements are involved in approximately 10% of hereditary non-polyposis colorectal cancer (HNPCC) families, and in most of the rearrangements, exon 1 is deleted. We scanned by quantitative multiplex polymerase chain reaction (PCR) of short fluorescent fragments (QMPSF) 200 kb of genomic sequences upstream of the MSH2 transcription initiation site in 21 HNPCC families with exon 1 deletions. This QMPSF scan revealed 12 distinct 5' breakpoints located up to 200 kb upstream of the MSH2 transcription initiation site.

View Article and Find Full Text PDF

The absence of detectable germline TP53 mutations in a fraction of families with Li-Fraumeni syndrome (LFS) has suggested the involvement of other genes, but this hypothesis remains controversial. The density of Alu repeats within the TP53 gene led us to search genomic rearrangements of TP53 in families without detectable TP53 mutation. To this aim, we adapted the quantitative multiplex PCR of short fluorescent fragments (QMPSF) method to the analysis of the 11 exons of TP53.

View Article and Find Full Text PDF

To estimate the relative frequency of mismatch repair genes, rearrangements in hereditary nonpolyposis colorectal cancer (HNPCC) families without detectable mutations in MSH2 or MLH1, we have analyzed by multiplex PCR of short fluorescent fragments MSH2, MLH1, and MSH6 in 61 families, either fulfilling Amsterdam criteria or including cases of multiple primary cancers belonging to the HNPCC spectrum. We detected 13 different genomic rearrangements of MSH2 in 14 families (23%), whereas we found no rearrangement of MLH1 and MSH6. Analysis of 31 other families, partially meeting Amsterdam criteria, revealed no additional rearrangement of MSH2.

View Article and Find Full Text PDF