Reproductive counselling in translocation carriers

: new answers to an old question?

Abstract

Chromosomes are the carriers and transporters of most of our genetic material. In most of us , 46 chromosomes per cell are present and these chromosomes have a well-defined structure. Some people have a different number of chromosomes in their cells -called numerical anomalies- whereas in others some chromosomes have a different structure, called structural anomalies. Robertsonian and reciprocal translocations are examples of structural chromosomal aberrations and they occur in the general population with a frequency of 1/1000 to 1/700. However, they are diagnosed more frequently in persons with recurrent miscarriages or reduced fertility. Couples in which one of the partners carries a balanced translocation often seek genetic advice with respect to their reproductive chances and options . The contacts with these couples at the Centre for Medical Genetics triggered the interest towards the reported research.
We retrospectively looked at the outcomes of Preimplantation Genetic Diagnosis (PGD) and prenatal diagnosis in couples carrying a Robertsonian or reciprocal translocation. We observed that PGD is a valuable option for these couples, especially for the ones suffering from infertility . On the other hand, prenatal diagnosis in ongoing pregnancies without PGD, showed normal/ balanced chromosomal results in the majority of the cases.
Comparison of the characteristics and the results in all groups, made us conclude that several factors have to be taken into account when counselling these couples. The type of translocation, the gender of the carrier as well as the personal and familial reproductive history are important elements to consider. However, reproductive counselling is more than a sum of medical facts and the final decision stays with the couple.

Date of Award	7 Jun 2016
Original language	English
Awarding Institution	Vrije Universiteit Brussel
Supervisor	Mary-Louise Bonduelle (Promotor), Ingeborg Liebaers (Co-promotor), Catherine Staessen (Co-promotor), Hilde Van De Velde (Jury), Michel De Vos (Jury), Leonardo Gucciardo (Jury), Christiaan Van Schravendijk (Jury), Christine De Die (Jury) & Bettina Blaumeiser (Jury)