Research by Instituto Bernabeu published in the journal JARG studies the reasons why chromosomal alterations occur in the embryos of some young women.

Scientific journal “Journal of Assisted Reproduction and Genetics” has published scientific research carried out by the Instituto Bernabeu IBbiotech genetics laboratory entitled “Identification of novel candidate genes associated with meiotic aneuploidy in human embryos by whole-exome sequencing”. This is a study carried out with the aim of finding out why in certain young patients there are high rates of embryonic aneuploidy. These alterations occur when instead of two copies for each chromosome there are more or less copies, which alters the genetic material of the embryo’s cells.

These chromosomal alterations are frequent in human embryos and these errors increase in women of advanced maternal age. However, there is a group of young patients in whom a high rate of aneuploidy has been detected, when due to their age is not usual for this to occur. The genetics laboratory scientific director and lead author of the study, Dr Belén Lledó, points out that the aneuploidy rate varies among in vitro fertilization (IVF) patients with a given age or group. On the other hand, recent studies have shown that there are genetic variants associated with the risk of embryonic aneuploidy.

Instituto Bernabeu’s study has identified genetic variants that could pose a risk of embryonic aneuploidy. Dr Lledó explains that this is the first time the whole clinical exome (WES: Whole Exome Sequencing) has been analysed in both members of the couple, with the aim of identifying the paternal or maternal origin of the embryonic aneuploidy genetic risk. Until now, studies have analysed certain variants but only in the woman.

This study’s importance lies in the identification of new candidate genes and variants not previously associated with embryonic aneuploidy involved in important biological processes related to cell division and chromosome segregation. “The information presented in this study could help in molecular diagnosis and contribute to the understanding of the mechanisms involved in embryonic aneuploidy”, says Dr Lledó. The scientist also confirms that the exome study can be an efficient tool to identify patients with an embryonic aneuploidy result higher that expected for maternal age and allow individualized genetic counselling prior to treatment. At the same time, it is an improvement in success rates by reducing the patients’ treatment duration.

This research was selected by the European Society of Human Reproduction and Embryology (ESHRE) Scientific Committee as a featured poster at the ESHRE congress in Copenhagen (Denmark) at the end of June 2023.

Identification of novel candidate genes associated with meioticaneuploidy in human embryos by whole‑exome sequencing

B. Lledo, A. Marco, R. Morales, J.A. Ortiz, E. García-Hernández, F.M. Lozano, A. Cascales, J. Guerrero, A. Bernabeu, R. Bernabeu