This issue’s cover features companion papers that exemplify how understanding a rare disease can inform treatment strategies in other conditions.

Fassihi et al. and Nakazawa et al. report on the C-terminal deletion of transcription factor TFIIH-p52 subunit as a cause of xeroderma pigmentosum.

The cover art was created using PyMOL; TFIIH-p52 subunit (blue; C-terminus in white). Image credit: Keiko Itano.

https://www.jci.org/articles/view/195731 https://www.jci.org/articles/view/195732

¹National Xeroderma Pigmentosum Service, Rare Disease Centre, Guy’s and St Thomas’ NHS Trust, London, United Kingdom.

²Department of Molecular Genetics, Nagoya University Graduate School of Medicine, Nagoya, Japan.

³Department of Genetics, Research Institute of Environmental Medicine, Nagoya University, Nagoya, Japan.