QF-PCR and MLPA: a reliable molecular system to detect chromosomal alterations in miscarriages

The aim of this study was to assess the efficacy of the quantitative fluorescent-polymerase chain reaction (QF-PCR) and multiplex ligation-dependent probe amplification (MLPA) combined system to detect chromosome alterations in miscarriage products, as an alternative to conventional cytogenetic testing.

This study was conducted between 2011 and 2015 on 264 samples, analyzed using the combined system: QF-PCR/MLPA. This approach first analyzed miscarriage products for chromosomes 13, 18, 21, X and Y, using QF-PCR analysis; in case of ovular fragments, an analysis of maternal DNA was carried out in order to establish the origin of material. Whenever fetal origin was determined, MLPA analysis on the subtelomeric regions was car- ried out.

On 264 miscarriages analyzed, 229 were of fetal origin and produced the following results: 53.7% normal and 46.3% pathological. Of the latter, 74.4% were autosomal aneuploidies, 10.4% triploidies, 8.5% sex chromosomal aneuploidies, 3.7% structural alterations, and 2.7% multiple aneuploidies. Results from QF-PCR were obtained from all samples, whereas unambiguous MLPA re- sults were obtained in about 90% of all cases.

This approach results being highly effective for examining all chromosome aneuploidies, triploidies, as well as structural unbalanced alterations in the subtelomeric regions.