Prenatal Ultrasound Suspicion of Cystic Fibrosis in a Multiethnic Population: Is Extensive CFTR Genotyping Needed?

In families without a Cystic Fibrosis (CF) history, fetal ultrasound bowel abnormalities can unexpectedly reveal the disease. Isolated or in association, the signs can be fetal bowel hyperechogenicity, intestinal loop dilatation and non-visualization of fetal gallbladder. In these cases, search for CF transmembrane conductance regulator (CFTR) gene mutations is part of the recommended diagnostic practices, with a search for frequent mutations according to ethnicity, and, in case of the triad of signs, with an exhaustive study of the gene. However, the molecular diagnosis remains a challenge in populations without well-known frequent pathogenic variants. We present a multiethnic cohort of 108 pregnancies with fetal bowel abnormalities in which the parents benefited from an exhaustive study of the CFTR gene. We describe the new homozygous p.Cys1410* mutation in a fetus of African origin. We did not observe the most frequent p.Phe508del mutation in our cohort but evidenced variants undetected by our frequent mutations kit. Thanks to the progress of sequencing techniques and despite the difficulties of interpretation occasionally encountered, we discuss the need to carry out a comprehensive CFTR study in all patients in case of fetal bowel abnormalities.

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Clinical and genetic characteristics of rare pathogenic variants of the CFTR gene in Russian patients with cystic fibrosis

Russian Pulmonology ◽

10.18093/0869-0189-2021-31-2-148-158 ◽

2021 ◽

Vol 31 (2) ◽

pp. 148-158

Author(s):

A. Yu. Voronkova ◽

Yu. L. Melyanovskaya ◽

N. V. Petrova ◽

T. A. Adyan ◽

E. K. Zhekaite ◽

...

Keyword(s):

Cystic Fibrosis ◽

Genetic Variants ◽

Pancreatic Insufficiency ◽

Protein Energy Malnutrition ◽

Molecular Genetic ◽

Clinical Manifestations ◽

Cftr Gene ◽

Genetic Characteristics ◽

Missense Variants ◽

Pathogenic Variants

The variety of clinical manifestations of cystic fibrosis is driven by the diversity of the CFTR gene nucleotide sequence. Descriptions of the clinical manifestations in patients with the newly identified genetic variants are of particular interest.The aim of this study was to describe clinical manifestations of the disease with the newly identified genetic variants.Methods. Data from Registry of patients with cystic fibrosis in the Russian Federation (2018) were used. The data review included three steps — the search for frequent mutations, Sanger sequencing, and the search for extensive rearrangements by MLPA. 38 pathogenic variants were identified that were not previously described in the international CFTR2 database. We selected and analyzed full case histories of 15 patients with 10 of those 38 pathogenic variants: p.Tyr84*, G1047S, 3321delG, c.583delC, CFTRdele13,14del18, CFTRdele19-22, c.2619+1G>A, c.743+2T>A, p.Glu1433Gly, and CFTRdel4-8del10-11.Results. A nonsense variant p.Tyr84* was found in 5 patients (0.08 %). Two missense variants c.3139G>A were found in 2 siblings (0.03 %). The c.4298A>G was found in 1 patient. Other variants were detected in a single patient (0.02 %) each. They included two variants of a deletion with a shift of the reading frame 3321delG and c.583delC, two splicing disorders c.2619+1G>A and c.743+2T>A, three extended rearrangements CFTRdele19-22, CFTRdele13,14del18, and CFTRdel4-8del10-11. The last two variants include 2 rearrangements on one allele, which cause the severe course in two young children. 8 of the 10 variants are accompanied by pancreatic insufficiency (PI). Among patients with p.Tyr84*, one had ABPA, one had liver transplantation, and all had Pseudomonas aeruginosa infection. Nasal polyps were diagnosed in 2 patients with p.Tyr84*, 1 with G1047S, 1 with CFTRdel4-8del10-11, and 1 patient with 3321delG, who also had osteoporosis and cystic fibrosis-related diabetes (CFRD). 2 patients with PI with 3321delG and CFTRdel4-8del10-11 genetic variants, and 1 with PI with p.Glu1433Gly genetic variant had severe protein-energy malnutrition (PEM).Conclusion. Clinical manifestations of previously undescribed CFTR genetic variants were described. 5/10 genetic variants should be attributed to class I, 3/10 – to class 7 of the function classification of pathogenic CFTR gene variants associated with transcription and translation disruptions. Class of the identified missense variants c.3139G>A and c.4298A>G has not been established and requires further functional, cultural, and molecular genetic studies.

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Identification of Unique Pattern of CFTR Gene Mutations in Cystic Fibrosis in an Ethnic Kashmiri Population (North India)

Journal of Genetic Syndromes & Gene Therapy ◽

10.4172/2157-7412.1000260 ◽

2015 ◽

Vol 06 (02) ◽

Cited By ~ 1

Author(s):

Arshad A Pandith

Keyword(s):

Cystic Fibrosis ◽

Gene Mutations ◽

North India ◽

Cftr Gene ◽

Unique Pattern ◽

Kashmiri Population ◽

Cftr Gene Mutations

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The Frequency of Familial Mediterranean Fever Gene Mutations and the Correlations between Phenotype and Genotype in Turkish Children

Asian Journal of Pediatric Research ◽

10.9734/ajpr/2020/v4i230145 ◽

2020 ◽

pp. 20-26

Author(s):

Hakan Erdogan ◽

Ayse Cavidan Sonkur ◽

Orhan Görükmez ◽

Ayse Erdogan ◽

Dilek Damla Saymazlar ◽

...

Keyword(s):

Familial Mediterranean Fever ◽

Mutation Screening ◽

Mefv Gene ◽

Gene Mutations ◽

Retrospective Case ◽

Turkish Children ◽

Pathogenic Variants ◽

Frequent Mutations ◽

Training And Research ◽

Mediterranean Fever

Aim: Familial Mediterranian Fever is an autosomal recessive disease characterized by recurrent inflammatory attacks of serosal membranes. The aim of the current study was to determine the frequency of the Mediterranean fever (MEFV) gene pathogenic variants in 158 children (78 male, 80 female) diagnosed with Familial Mediterranean Fever (FMF) and to compare the phenotype-genotype correlation. Methods: In our retrospective case-control study, 158 FMF patients (78 males, 80 females) who were diagnosed with MEFV gene mutation in Bursa Yuksek Ihtisas Training and Research Hospital, Department of Pediatrics between January 2018 and June 2019 were included in the study. Mutation screening of the MEFV gene was performed for 12 mutations and the 8 most common mutations were taken into the study. Results: Abdominal pain (77.8%), fever (74%) and arthralgia (46.2%) were the most prevalent clinical features in our patients. The most frequent mutations were M694V, E148Q, V726A, M680I and P369S. In cases with M694 mutation, it was noted that the incidence of arthritis was 2.5 times, appendectomy frequency 3.1 times higher, and early diagnosis probability 3.2 times higher. The frequency of chest pain was 2.9 times higher in the M680I mutation, and the frequency of arthralgia was 2.2 times higher in the P369S mutation. Conclusion: Patient’s mutations in FMF patients are important for clinical expectations, and some mutations such as P369S are not as innocent as expected. However, reevaluation of phenotypes of mutations that are rare with more patients will be significant.

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Current Challenges in Cystic Fibrosis Screening

Archives of Pathology & Laboratory Medicine ◽

10.5858/2003-127-1133-ccicfs ◽

2003 ◽

Vol 127 (9) ◽

pp. 1133-1139 ◽

Cited By ~ 1

Author(s):

Elaine Lyon ◽

Christine Miller

Keyword(s):

Cystic Fibrosis ◽

Health Care Providers ◽

Patient Information ◽

Phenotypic Expression ◽

Gene Mutations ◽

Care Providers ◽

Idiopathic Pancreatitis ◽

Advantages And Disadvantages ◽

Bilateral Absence ◽

Cf Transmembrane Conductance Regulator

Abstract Content.—This article gives an overview of the symptoms and mutations associated with classic and atypical cystic fibrosis (CF). Current testing methods for mutation detection in CF are discussed. Objectives.—Review testing for CF, including American College of Medical Genetics and American College of Obstetrics and Gynecology guidelines and recommendations regarding population screening for CF. Describe symptomatic and mutational differences between patients with classic CF and atypical CF, including monosymptomatic conditions such as congenital bilateral absence of the vas deferens, idiopathic pancreatitis, and chronic sinusitis. Explain the concern about predicting the phenotypic expression of the condition from the genotype. Discuss the challenges of CF testing, including the preanalytic, analytic, and postanalytic phases. List the current methods for detecting CF transmembrane conductance regulator gene mutations, specifying the advantages and disadvantages of each. Describe the basic patient information necessary for laboratories to provide accurate risk assessments, such as ethnicity and family history, and reasons for the test being conducted (carrier or affected status). Results.—The technical challenges of detecting the 25 recommended mutations are being met by commercially available reagents. Challenges remain for the preanalytic and postanalytic phases. Only with accurate patient information can laboratories provide specific risk reductions on the basis of a negative genetic test result. Conclusion.—As health care providers become better informed about the recommendations for CF testing and laboratories continue to increase the sensitivities of their assays, patients will benefit from increased screening efficiency and accuracy. This will allow affected individuals to receive prompt and effective treatment and carriers to enjoy an expanded number of reproductive options.

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Structural analysis of CFTR gene in congenital bilateral absence of vas deferens

Clinical Chemistry ◽

10.1093/clinchem/41.6.833 ◽

1995 ◽

Vol 41 (6) ◽

pp. 833-835 ◽

Cited By ~ 6

Author(s):

P Jézéquel ◽

I Dorval ◽

P Fergelot ◽

B Chauvel ◽

A Le Treut ◽

...

Keyword(s):

Cystic Fibrosis ◽

Structural Analysis ◽

Vas Deferens ◽

Cftr Gene ◽

Bilateral Absence ◽

Frequent Mutations

Abstract Congenital bilateral absence of the vas deferens (CBAVD) is found in most males with cystic fibrosis (CF), but this malformation can be observed without any pulmonary or digestive features. We have analyzed 13 exons of the CF gene in a cohort of 25 CBAVD patients. Among the 50 chromosomes studied, 24 mutations were identified: delta F508 (14 cases), R117H (7 cases), R1070W (2 cases), 621 + 1 G --> T (1 case), and A1067V (1 case). Except for delta F508, the most frequent mutations (R117H, R1070W) were not observed in the CF group (109 patients) studied in our laboratory. We discuss the significance of these results.

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