Clinical Trial: Prenatal Screening for Imprinting Anomalies Implicated in Beckwith Wiedemann and Silver Russell Syndromes

Study Status: Active, not recruiting
Recruit Status: Active, not recruiting
Study Type: Interventional

Official Title: Prenatal Screening for Imprinting Anomalies Implicated in Beckwith Wiedemann and Silver Russell Syndromes

Brief Summary:

Losses of imprinting are involved in various syndromes. Those occurring in the 11p15 region lead to Beckwith-Wiedemann and Silver-Russell Syndromes. These losses of imprinting follow a mosaic pattern, rendering their detection difficult, especially given the scarcity of available DNA in amniotic fluid. Thus, in spite of growing demand, prenatal diagnosis (PND) for imprinting abnormalities of the 11p15 region is not available.

The recent development of a quantitative PCR method that permits the methylation index (MI) of imprinted regions to be calculated renders PND technically possible. Nevertheless, because of the mosaic nature of these anomalies, it is essential to verify that the methylation pattern of the 11p15 region obtained from the amniotic fluid matches that obtained from the blood.


Detailed Summary:

To evaluate the agreement between the methylation index of the 11p15 region obtained using DNA extracted from amniocytes and that extracted from cord blood leukocytes, by calculating the intraclass correlation coefficient (ICC).

Ancillary study :

This second part of the study aims to determine the standard of methylation index of the 11p15 region (inclusion of 100 additional patients). The use of amniotic liquid will allow to calculate :

  • the average of methylation index,
  • the value of the standard deviation
  • the inter-assay coefficient of variation for the test-used.

Sponsor: Assistance Publique - Hôpitaux de Paris

Current Primary Outcome: Methylation Index (MI) of the 11p15 region using DNA extracted [ Time Frame: 27 weeks ]

To evaluate the agreement between the MI of the 11p15 region obtained using DNA extracted from amniocytes and that extracted from cord blood leukocytes, by calculating the intraclass correlation coefficient (ICC).


Original Primary Outcome: Same as current

Current Secondary Outcome: MI using the placenta [ Time Frame: 27 weeks ]

To calculate the MI using the placentas of the same individuals and to evaluate its agreement with the MIs obtained above.


Original Secondary Outcome: Same as current

Information By: Assistance Publique - Hôpitaux de Paris

Dates:
Date Received: April 24, 2013
Date Started: May 2013
Date Completion: October 2016
Last Updated: August 23, 2016
Last Verified: August 2016