Laura Hercher in Scientific American:
For better or worse, genetic testing of embryos offers a potential gateway into a new era of human control over reproduction. Couples at risk of having a child with a severe or life-limiting disease such as cystic fibrosis or Duchenne muscular dystrophy have used preimplantation genetic testing (PGT) for decades to select among embryos created through in vitro fertilization (IVF) for those that do not carry the disease-causing gene. But what new iteration of genetic testing could tempt healthy, fertile couples to reject our traditional time-tested and wildly popular process of baby making in favor of hormone shots, egg extractions and DNA analysis?
A California-based start-up called Orchid Biosciences claims it has an answer to that question. The company offers prospective parents genetic testing prior to conception to calculate risk scores estimating their own likelihood of confronting common illnesses such as heart disease, diabetes, and schizophrenia and the likelihood that they will pass such risks along to a future child. Parents-to-be can then use IVF, along with Orchid’s upcoming embryo screening package, to identify the healthiest of their embryos for a pregnancy.
Orchid aims to use PGT and IVF to expand what is already a thriving marketplace in screening tests for prospective parents. Initially, the only people offered tests to prevent genetic disease in the next generation were those whose ancestry put them at higher risk for a specific condition, such as Tay-Sachs disease in the Ashkenazi Jewish population. The first genetic screen intended for universal use and covering a wide range of diseases was introduced by Counsyl (now part of Myriad Genetics) in 2010. Today carrier screening is a $1.7-billion industry. These tests search for genetic problems that otherwise come to light only after the birth of an affected child. But diseases caused by a single gene are rare. Most children are born healthy, and most couples who do carrier screening come away reassured.