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Children born after ART at increased risk of congenital malformation

January 22, 2016

The scientists are now trying to find out the origin of parental infertility for each child born after ART who has been affected by major malformation or epigenetic disorders. "With this knowledge, we can better establish the origin of the malformation and whether it is more likely to be related to parental infertility or the ART procedure itself", said Dr. Viot. "We already know that imprinting disorders - where the mechanism in which gene expression depends on parental origin - are clearly more frequent in our cohort than in the general population."

Imprinting disorders are all acquired because of either a maternal or paternal deletion on a chromosome, through inheritance of both chromosomes of a pair from only one parent, through mutations in some imprinted genes, or because of loss or gain of methylation (a process which is normally removed during zygote formation and re-established through successive cell divisions during development. "The prevalence of the imprinting disorder Beckwith Wiedemann syndrome in our cohort is six times higher than we would expect in the general population, and for retinoblastoma the prevalence among ART children is 4.5 higher than in the general population", said Dr. Viot.

"These results could be due to the effect of a number of different mechanisms. They could be due to the infertility itself, the ovarian stimulation for supernumerary oocyte production, the in vitro maturation of oocytes, the use of ICSI (direct injection of sperm), the culture media, the cryopreservation of gametes and embryos - we just don't know at present. Finding this out will be a major step towards improving the health of children born after ART."

Source: European Society of Human Genetics