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2014, Number 1

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Revista Cubana de Obstetricia y Ginecología 2014; 40 (1)

Variants of heterochromatin and euchromatin in cytogenetic prenatal diagnosis

Soriano-Torres M, Morales RE, Rojas BI, Méndez RLA

Language: Spanish
References: 34
Page: 79-88
PDF size: 221.52 Kb.


ABSTRACT

Some changes in chromosome morphology, which are detected in cytogenetic diagnostics, are not associated with clinical defects presenting a dilemma for the genetic counsellor, especially during prenatal diagnosis; this is the reason why a proper discrimination between innocuous variants and true anomalies is crucial to allow precise counselling. Polymorphisms of heterochromatin are identified usually by specific banding techniques and considered as Mendelian variations without a clinical significance. Likewise, it has been exposed in the literature the presence of variants in euchromatic regions that after a detailed analysis turns out to be of benign nature. Due to the current importance of this issue it is necessary to propose a protocol to follow in our laboratories every time a chromosome variant is detected while performing a prenatal analysis and supported by experienced specialist in our field. The goal of this work is to present a review of the literature about how a finding of a chromosome variant is handled and the suggestions given for a more proper management.


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