Carme Fuster

Rapid prenatal diagnosis of common chromosome aneuploidies by QF‐PCR, results of 9 years of clinical experience

Despite being deliberately targeted to common chromosome aneuploidies, the rapid quantitative fluorescent polymerase chain reaction (QF‐PCR) tests can detect the majority of chromosome abnormalities in prenatal diagnosis. The main advantages of this assay are low cost, speed and automation allowing large‐scale application.

Health Changes in Fishermen 2 Years After Clean-up of the Prestige Oil Spill

BACKGROUND In 2002, the oil tanker Prestige spilled more than 67,000 tons of bunker oil, heavily contaminating the coast of northwestern Spain. OBJECTIVE To assess respiratory effects and chromosomal damage in clean-up workers of the oil spill 2 years after the exposure. DESIGN Cross-sectional study. SETTING Fishermen cooperatives in coastal villages. PARTICIPANTS Local fishermen who were highly exposed (n = 501) or not exposed (n = 177) to oil 2 years after the spill. MEASUREMENTS Respiratory symptoms; forced spirometry; methacholine challenge; markers of oxidative stress (8-isoprostane), airway inflammation (interleukins, tumor necrosis factor-α, and interferon-γ), and growth factor activity in exhaled breath condensate; and chromosomal lesions and structural alterations in circulating lymphocytes. RESULTS Compared with nonexposed participants, persons exposed to oil were at increased risk for lower respiratory tract symptoms (risk difference, 8.0 [95% CI, 1.1 to 14.8]). Lung function did not significantly differ between the groups. Among nonsmoking participants, exposed individuals had higher exhaled 8-isoprostane levels than nonexposed individuals (geometric mean ratio, 2.5 [CI, 1.7 to 3.7]), and exposed individuals with lower respiratory tract symptoms had higher 8-isoprostane levels than those of exposed individuals without symptoms. Exposed nonsmoking participants also had higher levels of exhaled vascular endothelial growth factor (risk difference, 44.8 [CI, 27.9 to 61.6]) and basic fibroblast growth factor (risk difference, 16.0 [CI, 3.5 to 28.6]). A higher proportion of exposed participants had structural chromosomal alterations (risk difference, 27.4 [CI, 10.0 to 44.8]), predominantly unbalanced alterations. The risk for elevated levels of exhaled 8-isoprostane, vascular endothelial growth factor, and basic fibroblast growth factor and structural chromosomal alterations seemed to increase with intensity of exposure to clean-up work. LIMITATIONS The clinical significance of exhaled biomarkers and chromosomal findings are uncertain. The association between oil exposure and the observed changes may not be causal. The findings may not apply to spills involving other types of oil or to different populations of oil spill workers. CONCLUSION Participation in clean-up of a major oil spill was associated with persistent respiratory symptoms, elevated markers of airway injury in breath condensate, and chromosomal damage.

Rapid prenatal diagnosis by QF-PCR: evaluation of 30,000 consecutive clinical samples and future applications.

Abstract:  Rapid prenatal diagnoses of major chromosome abnormalities can be performed on a large scale using highly polymorphic short tandem repeats (STRs) amplified by the quantitative fluorescent polymerase chain reaction (QF‐PCR). The assay was introduced as a preliminary investigation to remove the anxiety of the parents waiting for the results by conventional cytogenetic analysis using amniotic fluid or chorionic cells. However, recent studies, on the basis of the analyses of several thousand samples, have shown that this rapid approach has a very high rate of success and could reduce the need for cytogenetic investigations. Its high efficiency, for example, allows early interruption of affected fetuses without the need of waiting for completion of fetal karyotype. The main advantages of the QF‐PCR are its accuracy, speed, automation, and low cost that allows very large number of samples to be analyzed by few operators. Here, we report the results of using QF‐PCR in a large series of consecutive clinical cases and discuss the possibility that, in a near future, it may even replace conventional cytogenetic analyses on selected samples.

Chromosome abnormalities in peripheral blood lymphocytes from untreated Hodgkin's patients

SummaryWe describe the presence of a high frequency of spontaneous chromosome aberrations in lymphocytes from six untreated patients with Hodgkins disease. The characteristics of the chromosome abnormalities observed suggest the existence of a certain degree of chromosome instability in these cases, that could be a predisposing factor for the development of malignancies.

Assessment of new markers for the rapid detection of aneuploidies by quantitative fluorescent PCR (QF–PCR)

Rapid prenatal diagnoses of major chromosome aneuploidies have been achieved successfully using quantitative fluoresent PCR (QF–PCR) assays and small tandem repeat (STR) markers. Here we report the results of evaluating the use of previously untested X‐linked STRs, (DXS6803) and (DXS6809), together with modified amelogenin (AMXY) sequences and the X22 marker that maps in the pseudoautosomal region PAR2 on the long arm of the X and Y chromosomes. These markers will allow prenatal diagnoses of sex chromosome aneuploidies such as 45,X (pure Turner Syndrome), 47,XXY and 47,XYY, while assessing the sex of the fetuses. Data are also presented concerning the difficulties associated with the evaluation of the frequencies of the various types of sub‐populations of cells in amniotic fluid samples collected from fetuses with sex chromosome mosaicism. The results of evaluating the use of new markers for the rapid diagnosis of aneuploidies affecting chromosomes 21,18 and 13 are also presented. Three chromosome 21 specific STRs have been found to produce trisomic triallelic or diallelic patterns from all amniotic samples retrieved from fetuses with Down Syndrome. Since all samples tested were amplified and no false positive or negative results were observed, the present results confirm the diagnostic value of QF–PCR for the prenatal detection of major numerical chromosome disorders.

Persistent respiratory symptoms in clean-up workers 5 years after the Prestige oil spill

Objectives Fishermen who had participated in clean-up activities of the Prestige oil spill showed an excess risk of respiratory symptoms 1–2 years later, but the long-term persistence of these health effects is unclear. The aim of this study was to evaluate the persistence of these respiratory symptoms 5 years after clean-up work. Methods Subgroups of 501 fishermen who had been exposed to clean-up work and 177 non-exposed individuals were re-interviewed by telephone in 2008, including the same symptom questions as in the initial survey. Associations between participation in clean-up work and respiratory symptoms were assessed using log-binomial and multinomial regression analyses adjusting for sex, age and smoking. Results Information from 466 exposed (93%) and 156 non-exposed (88%) fishermen was obtained. The prevalence of lower respiratory tract symptoms (including wheeze, shortness of breath, cough and phlegm) had slightly decreased in both groups, but remained higher among the exposed (RR 1.4, 95% CI 1.1 to 1.9). The risk of having persistent respiratory symptoms (reported both at baseline and at follow-up) increased with the degree of exposure: RR ratio 1.7 (95% CI 0.9 to 3.1) and 3.3 (95% CI 1.8 to 6.2) for moderately and highly exposed, respectively, when compared with those without any symptoms. Findings for nasal symptoms and for respiratory medication usage were similar. Conclusions Participation in clean-up activities of oil spills may result in respiratory symptoms that persist up to 5 years after exposure. Guidelines for preventive measures and a continued surveillance of clean-up workers of oil spills are necessary.

Analysis of kidney tumors by comparative genomic hybridization and conventional cytogenetics

Comparative genomic hybridization (CGH) and conventional cytogenetic karyotyping were used to screen for losses and gains of DNA sequences along chromosomes in ten renal tumors (RCC) of different histologic types (clear-cell RCC, papillary RCC, and one oncocytoma). Loss of 3p was the most common change in clear-cell RCC. All papillary tumors, either adenomas or carcinomas revealed gains of chromosomes 7 and 17q without limitation to size and grade. Homozygotic loss of the pseudoautosomal Xp or Yp region was detected in three RCC tumors. A dicentric (Y;14) was present as the sole chromosome abnormality in the oncocytoma. Both techniques showed concordant results in tumors with homogeneous karyotype. However, in tumors with several composite clones some discrepancies were observed, especially in cases of clear-cell RCC where chromosomal abnormalities present in a low number of metaphases could not be detected by CGH.

Comparative genomic hybridization analysis of transitional cell carcinomas of the renal pelvis.

We used comparative genomic hybridization to analyze 10 primary tumor samples from patients with transitional cell carcinoma of the renal pelvis. The most frequent loss was located at 9q, that is, in 50% of the tumors. Gains of DNA sequences were most frequently observed in chromosome regions 1q21 approximately q23, 2p23 approximately p25, 8q21.1 approximately q22 and in the whole chromosome 20. High level amplifications at 1q21 approximately q25, 6p22 approximately p23, 8q21 approximately q22, 8q22 approximately q24.1, 11q13, and 12q14 approximately q21 were detected. Most of these regions have previously been reported to be involved in transitional cell carcinoma of the bladder, thus confirming the importance of an increasing number of chromosome imbalances in the development and progression of this type of tumors.

Chromosomal instability in breast cancer patients

SummaryWe have carried out cytogenetic studies, using the G-banding technique, in peripheral blood lymphocytes of 10 patients affected by breast carcinoma. The frequency of aberrant metaphases (7.36%) is significantly different from that of our laboratory controls (3.76% of aberrant metaphases) but not from that detected in patients suffering from bladder cancer (10.64%) and Hodgkins disease (11.03%), two conditions that have previously been described as chromosomally unstable. Our results suggest that breast carcinoma patients show a degree of chromosomal instability that could be related to a predisposition to neoplastic disease.

Chromosome instability in bladder carcinoma patients.

The relationship between the presence of a high frequency of chromosome aberrations and a predisposition to cancer has been well established in the so-called chromosome instability syndromes. Chromosome instability is also present in a variety of patients affected by cancer, and sometimes in their healthy relatives. We present a cytogenetic study carried out in lymphocytes from 13 untreated bladder carcinoma patients (only four of them had a history of occupational exposure to mutagens). Percentages of aberrant metaphases were significantly higher in cancer patients than in controls. Of the total number of chromosome aberrations in cancer patients, 67.16% corresponded to major structural chromosome abnormalities, while 25.37% were gaps or breaks. Numerical abnormalities represented 7.46% of the total. The bands more frequently involved in chromosome rearrangements were 5q31 and 1q32. Our results tentatively indicate that a significant proportion of patients with bladder carcinoma may have an underlying inherent chromosome instability. An age effect cannot be excluded, but we did not find significant differences between patients over 50 years of age and patients under 50 years of age.