The transcervical collection of fetal cells for early and minimally invasive prenatal diagnosis

Abstract
In the last decade, many studies have documented the presence of fetal cells in samples collected transcervically in early pregnancy. Since fetal cells are present in these samples as early as 7 weeks\' gestation, and some of the methods for sample collection (i.e. mucus collection) appear absolutely non-invasive, this approach is regarded as an earlier and safer alternative to all the techniques currently used for prenatal genetic diagnosis. Our studies in this field have contributed to assess the efficacy of different methods for the collection and analysis of transcervical cell samples; all in all it seems that intrauterine lavage the only valuable option, since fetal cells are present in most samples and at a very high rate. In addition, our experience shows that fetal cells in these samples can be reliably identified, sorted under microscope, and then analysed by many different procedures among which QF-PCR is probably the most promising; indeed, this latter technique enables the rapid and simultaneous assessment of the chromosomes most commonly involved in aneuploidies. Further work is required to assess the impact of transcervical cell sampling, and notably of intrauterine lavage, in continuing pregnancies before the possible clinical use of these techniques.

Key words
Células transcervicales, diagnóstico no invasivo, prenatal, FISH, PCR, reacción de cadena de polimerasa

Bibliografía del artículo

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