July 1, 2022

New test for 15,000 genetic diseases in embryos

A quick, simple and cheap method

A one-step test for
about 15,000 genetics diseases could be available within a
year. Doctors will be able to create IVF embryos, screen them
for conditions such as cystic fibrosis, Huntington’s disease and some
types of cancer, autism and mental retardation, and discard any
embryos which carry the genes. The test will probably cost about
£2,500 for each test.

Researcher Gary
Harton, of the Genetics & IVF Institute in the US, told the
European Society of Human Reproduction and Embryology in Amsterdam
that the test used karyomapping, "a universal method for
analysing the inheritance of genetic defects in the preimplantation
embryo without any prior patient or disease specific test
development, which often delays patient treatment."

Karyomapping would
also be quicker and cheaper than pre-implantation genetic diagnosis
(PGD). Currently, developing a PGD test for a single gene defect can
take weeks or months, because scientists have to identify the exact
patient or disease-specific genetic mutation first before screening
for it. This is labour-intensive and costly. By contrast,
karyomapping can be carried out without extended pre-test
development. The process now takes about three days but Mr Harton and
his colleagues believe this could be reduced to between 18 and 24
hours.

Critics who spoke to
London’s Daily Mail said that it was wrong to create embryos
and destroy them just because they are not healthy. Cures will also
be found for more and more diseases in years to come. In any case,
they say it is better to have a healthy life for 20 or 40 years —
before a genetic disease like Alzheimer’s kicks in — than never to
live at all. Josephine Quintavalle, of the campaign group Comment on
Reproductive Ethics, added the long-term health effects of testing
embryos were unknown: "I think the qualities that people look
for have very little to do with what makes a good and loving human
being." ~ Science Daily, July 1; Daily Mail, July 1