A controversial embryo screening technique is at the centre of new safety fears about its long-term effects.
Although pre-implantation genetic diagnosis (PGD) is available privately in the UK and on the NHS in some circumstances, it has never been subject to rigorous long-term studies.
Now a Chinese study conducted on mice has revealed memory decline in adulthood, sparking fears that PGD testing can increase the risk of offspring developing neurodegenerative disorders.
PGD is applied to IVF embryos which are thought to be at risk of inheriting a genetic illness from their parents.
The technique involves removing a cell from very early stage embryos to test for genetic abnormalities.
Only those embryos free from genetic defects are then implanted in the womb to be brought to birth. The less healthy embryos are destroyed.
The Chinese study, published in the journal Molecular and Cellular Proteomics, found that successful births from tested mouse embryos were significantly lower than from those which had not been tested.
Once fully grown, the mice tested as embryos had, on average, higher body weight and poorer memory in maze tests.
The team behind the experiment concluded that more studies into the possible long-term adverse effects of PGD are required.
Study co-author Yang Yu said: “This study indicated an increased relative risk of neurodegenerative disorders in the offspring generated.
More studies should be performed to address the possible adverse effects.”
Pro-life groups have opposed PGD testing, saying that it encourages the destruction of ‘imperfect’ embryos.
Josephine Quintavalle of campaign group Comment on Reproductive Ethics responded to the new study, saying: “Adult desire to have a child at any cost should never be achieved at the expense of the welfare of the resulting child.”
Reservations about the safety of PGD were raised during debates on the Human Fertilisation and Embryology Bill in the House of Lords last year.
Voicing concerns about the potential role of such tests in the creation of ‘saviour siblings’, Baroness O’Cathain said: “the longer-term consequences of the technology involved—pre-implantation genetic diagnosis or PGD—are unknown.”
