Limitaciones de los estudios de genética molecular en el proceso diagnóstico de fibrosis quística

Alicia Vaglio; Lucilla Pizzo; Andrea Quadrelli; Rosario Gueçaimburú; Sinthia Pagano; Roberto Quadrelli

Authors

Alicia Vaglio Instituto de Genética Médica (IGM). Médica Pediatra Genetista
Lucilla Pizzo Instituto de Genética Médica (IGM). Licenciada en Bioquímica
Andrea Quadrelli Instituto de Genética Médica (IGM). PhD. en Antropología. Licenciada en Biología
Rosario Gueçaimburú Instituto de Genética Médica (IGM). Médica Pediatra Genetista
Sinthia Pagano Instituto de Genética Médica (IGM). PhD. Química Farmacéutica
Roberto Quadrelli Instituto de Genética Médica (IGM). Académico. Médico Genetista

Keywords:

CYSTIC FIBROSIS

Abstract

Introduction: cystic fibrosis is an autosomal recessive hereditary disease caused by mutations of the gene which encodes a protein with a CFTR chloride channel function. It appears as a multi-organ disease and is characterized by a great clinical heterogeneity. There are patients who do not evidence the classic clinical characteristics and are described as atypical or non-classic cystic fibrosis. Diagnosis is based on a consistent clinical phenotype and evidence of dysfunction in the CFTR channel and/or in the identification of two mutations causing cystic fibrosis. None of these definitions is enough in itself to confirm diagnosis.
Objectives: to show a few limitations on the molecular genetic studies in the cystic fibrosis diagnostic process.
Method: five clinical cases of children referred with clinical data of probable cystic fibrosis were considered, and they were requested a genetic study to confirm diagnosis.
Results: studies conducted do not enable the confirmation of cystic fibrosis diagnosis and neither do they allow discarding a possible diagnosis of atypical cystic fibrosis.
Conclusions: in most cases the diagnosis of cystic fibrosis is clear and genetic studies enable the confirmation of diagnosis, genetic counseling and the final prenatal diagnosis. However, use and interpretation of genetic analysis result in several difficulties regarding the clinical and paraclinical characteristics of patients, technical limitations and choosing the mutations to be analysed, especially in the case of atypical cystic fibrosis. The present study shows the challenge faced by clinicians when interpreting a molecular result to incorporate it into the cystic fibrosis diagnostic process.

References

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