Study on Genetic Testing for Kidney Disease in Embryos Highlights Access, Coverage Issues

An analysis of preimplantation genetic testing trends in the Netherlands, used to identify genetic defects in embryos so that parents can avoid passing mutations to children, shows that people with devastating kidney diseases have increasingly opted for counseling and testing.

The availability of such services elsewhere raises ethical issues in the United States, because services might have to be paid out-of-pocket by US couples, thus creating disparities that need to be addressed, according to an accompanying editorial.

The results, appearing in the Clinical Journal of the American Society of Nephrology,¹ cover 25 years’ worth of genetic testing trends for kidney diseases in the Netherlands, where procedures are reimbursed as part of the national health care system. Counseling and testing for monogenic kidney diseases—those caused by mutations in a single gene—are performed before an embryo is implanted.

These processes are a relatively recent development, according to authors from University Medical Center Utrecht, who analyzed trends from January 1995 to June 2019. Most of the tests on embryos to screen for those with mutations for harmful kidney disease have been performed in the past decade, the authors said.

Conditions that couples checked for included autosomal dominant polycystic kidney disease, or ADPKD (38%), AIport syndrome (26%) and autosomal recessive polycystic kidney disease (9%), or ARPKD. One parent carrying a mutation for ADPKD gives each child a 50% chance of developing the disease, typically in adulthood; fluid-filled cysts form on the kidneys, which can grow from the size of a fist to the size of a football, bringing pain, complications, and increased risk of early death. Alport syndrome brings blood in the urine and abnormalities of the ears and eyes. While ARPKD has a lower chance of occurring—just 25% if both parents have the mutation—it can occur in infancy and children can die shortly after birth.

The Dutch team found that more couples received counseling for preimplantation genetic testing as the years passed. Over the entire study period, 98 couples were counseled, and 53% decided to proceed with testing, 38% chose not to proceed, and 9% had not decided what to do when the study ended in June 2019. Of the testing procedures, 45% were done to check for adult onset kidney disease, with the share rising to 50% at the end of the study. Among couples who had at least 1 preimplantation genetic testing cycle with an egg retrieval, 65% had at least 1 child born without kidney disease.

“Choosing how to start a family can be a complex decision if one has a genetic disease. Through [testing], a genetically unaffected pregnancy can be established, through an in vitro fertilization procedure,” Albertien M. van Eerde, MD, PhD, said in a statement. “Insights from our study may help doctors in informing patients with monogenic kidney disease who wish to start a family, and allow for adequate counseling.”

Over time, the number of kidney diseases that are known to be caused by a single gene has increased, so it is increasingly important to counsel patients on their options, the authors said.

In an accompanying editorial by authors from the University of Washington, Wylie Burke, MD, PhD, and Kathleen M. West, PhD, MS,² of the university’s Department of Bioethics and Humanities, noted there are numerous issues of access and ethics that must be examined—including the fact that the coverage situations are not the same.

“IVF and preimplantation genetic testing are not covered under most private insurance policies and are not available under federal health programs, except for Veterans Affairs coverage of service-related infertility,” Burke and West note. Professional practice guidelines afford considerable autonomy to physicians, but do so “only for parents of means.”

Those lacking access to testing may include those who lack coverage and the means to pay for such costs out of pocket, who may distrust the health system; thus, in the United States, the rise of such testing may exacerbate disparities. A more appropriate approach, they say, would cover testing in “rigorously selected” circumstances to address such inequities and avoid uses such as sex selection.

“Payers, including government programs, may be more likely to include coverage of preimplantation genetic testing if professional organizations offer stringent guidelines for its use that have the dual goal of preventing the birth of children with serious disease while supporting equitable access,” they wrote.

References

1. Snoek R, Stokman MF, Lichtenbelt KD, et al. Preimplantation genetic testing for monogenic kidney disease. Clin J Am Soc Nephrol. Published online August 27, 2020. doi: 10.2215/CJN.03550320.
2. Burke W, West KM. Preimplantation genetic testing for genetic kidney disease: addressing moral uncertainties and access inequity. Clin J Am Soc Nephrol. Published online on August 27, 2020. doi: 10.2215/CJN.11790720.