RESUMEN
BACKGROUND: The diagnosis of cystic fibrosis (CF) is established when characteristic clinical signs are coupled with biallelic CFTR pathogenic variants. No previously reported non-canonical splice site variants have to be considered as variants of uncertain significance unless their effect on splicing has been validated. METHODS: Two variants identified by next-generation sequencing were evaluated. We assayed their effects on splicing employing RNA analysis and real-time expression quantification from RNA obtained from the nasal epithelial cells of a patient with clinically suspected CF and of two patients with milder phenotypes (CFTR-related disorders). RESULTS: The variant c.164+2dup causes skipping of exon 2 (p.(Ser18_Glu54del)) and exon 2 plus 3 (p.(Ser18Argfs*16)) in CFTR mRNA. Exon 2 expression in the patient heterozygous for c.164+2dup was decreased to 7 % of the exon 2 expression in the controls. The synonymous variant c.1584G>A causes a partial skipping of exon 11. The exon 11 expression in the two patients heterozygous for this variant was 22 % and 42 % of that of the controls, respectively. CONCLUSION: We conclude that variant c.164+2dup affects mRNA processing and can be considered a CF-causing variant. The results of the functional assay also showed that the p.(Glu528=) variant, usually categorized as a neutral variant based on epidemiological data, partially affects mRNA processing in our patients. This finding would allow us to reclassify the variant as a CFTR-related variant with incomplete penetrance. RNA obtained from nasal epithelial cells is an easy and accurate tool for CFTR functional studies in patients with unclassified splice variants.
RESUMEN
BACKGROUND: Chronic obstructive pulmonary disease (COPD) is the fourth cause of death in western countries. Its final stage has clearly been forgotten by medical research in recent years. There exists consensus regarding the need to integrate palliative care in assisting these patients, but the difficulty in establishing a prognosis for the disease, establishing limits for life support measures, the lack of information about the disease's natural course and ignorance as to the most effective health-care structure for these patients' palliative treatment may be responsible for their late inclusion or non-inclusion in specific programmes. The main purpose of this work is to find out the natural background of patients with stage IV COPD and the main prognostic factors that influence these patients' survival. METHODS/DESIGN: Prospective observational study of a home patient cohort with stage IV COPD sent from Neumology consultations and Palliative Care Unit in La Paz Hospital in Madrid and Primary Care Health Centres in the area to the palliative care home support team. The goal is to study socio-demographic variables, prognosis, nutritional status, use of health resources, perceived quality of life, functionality, main symptomatology, use and effectiveness of opioids, adherence to treatment, prognostic information regarding the disease, information given by professionals, advance directives, social backup requirements and overburden level of the main caregiver. DISCUSSION: The HOLD study is a project aimed at finding out the prognostic factors and evolution of the disease COPD in its most advanced stage. The final goal is to improve the health and quality of life, in a personalised, integral way up to end of life and explore and foster communication with patients, as well as their participation and collaboration in decision-taking. The HOLD study can help us better understand what these patients' real palliative and care needs are, in order to more efficiently organise their treatment at end of life.
