Epigenetic sperm test sheds light on male infertility

The US start-up Episona has produced an epigenetic sperm test, which it claims can determine whether sperm will produce 'good' or 'poor' quality embryos.

The test, named 'Seed', was unveiled at the American Society for Reproductive Medicine's annual congress in Salt Lake City, Utah, this month, but it has received a cautious reception from fertility experts.

'Physicians have long relied on the traditional semen analysis as the sole option for determining the male's role in fertility,' said Episona president and CEO, Dr Alan Horsager. '[But this] offers little insight into the more complex factors related to male fertility or into the male's role in embryo development. Seed provides patients with previously missing information about their fertility and we believe this has the potential to transform fertility care.'

The test assesses DNA methylation at 480,000 regions across a sperm cell's genome. Environmental factors can alter the patterns of methylation in the genome – not just a man's own past and present environment, but also that of his own parents or grandparents.

Episona says that the regions selected are based on known methylation differences in the DNA of fertile and infertile sperm. After analysis of all the regions, a relative risk is assigned to each 'abnormal' location for either male-factor infertility or poor embryo development.  

But Dr Brian Abraham, a postdoctoral research fellow in epigenetics at the Massachusetts Institute of Technology, has reservations about the test. 'While the link between DNA methylation and sperm success has been studied, there is currently no consensus for how epigenomes contribute to this success,' he told the Genetic Literacy Project.

Episona co-founder Dr Douglas Carrell, an endocrinologist at the University of Utah, told STAT: 'My hope for the test is that we give [couples] more knowledge beforehand … One of the most heartbreaking things we see is people go through one cycle of IVF, have poor-quality embryos, and then go through a second cycle hoping it will be better.'

However, the company's website shows that they are marketing the test as 'a male fertility test that uses epigenetic data to improve your chances to get pregnant'.