Metacelsus

As we get closer to being able to grow human eggs from stem cells, it’s important to be sure that the eggs are high quality and safe enough to use for reproduction.[1] So, let’s discuss: what does an egg need to have in order to develop into a healthy baby...

Eggs are expensive, sperm are cheap. It’s a fundamental fact of biology . . . for now. Currently, embryo selection can improve any heritable trait, but the degree of improvement is limited by the number of embryos from which to select. This, in turn, is because eggs are rare. But...

Recently, a paper in Nature on building neural networks with DNA-based switches caught my attention.[1] The authors, Kevin Cherry and Lulu Qian, developed an interesting system that uses DNA base pairing to implement a trainable neural network. However, for me, what was even more interesting was a story hidden in...

Caviar is considered a luxury food, fetching up to hundreds of dollars per ounce for the most exclusive grades. But if you think caviar is expensive, consider that human eggs cost around $3,000 each at the low end, and much higher if you want to use a donor with good...

Preserving the memory, and the cells, of the best cat ever This story begins in May 2007. The Iraq War was in full swing, Windows Vista was freshly released,[1] and I was just 10 years old. My family’s beloved black cat, Lucy, had died. Devastated, I begged my parents: we...

This essay was written by @Metacelsus. In March 2023, a research team at Osaka University announced an extraordinary achievement: the production of viable eggs using cells taken from male mice. Building on years of research into stem cells and reproductive development,1 the researchers, led by Professor Katsuhiko Hayashi, developed a...

As you may know, I’m not a fan of cytomegalovirus (CMV), a herpesvirus that is usually asymptomatic, but causes all sorts of bad things like immune aging and birth defects. Over the last few months I’ve been following Moderna’s efforts at making a CMV vaccine. It seems like they’re having...