We often don’t think of them that way but reproductive cells like sperm and egg are also relatives of stem cells, and it turns out that there are stem cells that make the reproductive cells too like sperm stem cells.
Sperm and germ cell stem cells
DNMT3A-dependent DNA methylation is required for spermatogonial stem cells to commit to spermatogenesis, Nature. It makes sense that DNMT3 would be required for sperm development given the essential role of epigenetics in the process. We previously found a key role for histone H3.3 in sperm development as well. I wonder about a function for H3.3 in sperm stem cells as well.
Rat pups born from sperm artificially produced from stem cells, New Scientist. Similar work has previously been done in mice. It makes you wonder if someday decades down the road researchers will try to make people from gametes produced from stem cells. This could also bring CRISPR into play if someone decides to try to make CRISPR babies again (more on the fate of the scientist who did this in 2018 below). For instance, there are unique challenges to trying to gene-edit embryos precisely and safely. Some probably could be resolved by CRISPR’ing stem cells like sperm stem cells instead.
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Chemical reprogramming of human somatic cells to pluripotent stem cells, Nature. This is from a team led by Hongkui Deng. All chemical reprogramming made a big splash in 2013 but that was in mouse cells. Doing it in human cells seems like a big deal.
The creator of the CRISPR babies has been released from a Chinese prison, MIT Tech Review. It’s not often that we hear about scientists going to jail or then later being released from jail but He Jiankui, who made the so-called “CRISPR babies” is reportedly now out of prison. Chinese authorities locked him up not just for gene-editing babies without permission but also for violations of rules in the process.
It’s clearly a different situation, but even here in the U.S. federal authorities have been putting some scientists under investigation, usually for alleged failures to disclose foreign funding.
Editas Medicine Announces Dosing Of First Pediatric Patient In The BRILLIANCE Clinical Trial Of EDIT-101 For LCA10, PR. From the announcement: “Editas Medicine, Inc. (Nasdaq: EDIT), a leading genome editing company, today announced the administration of EDIT-101, an experimental CRISPR gene editing medicine, to the first pediatric patient enrolled in the BRILLIANCE clinical trial, which is designed to test the safety of EDIT-101 for the treatment of Leber congenital amaurosis 10 (LCA10), a CEP290-related retinal degenerative disorder. This marks the world’s first in vivo, or inside the body, dosing of a pediatric patient with a CRISPR gene editing experimental medicine.”