Merkel cells were discovered in the late nineteenth century and have long been suspected of playing a part in sensing light touch. However, this has never been entirely settled experimentally.
Ellen Lumpkin and Huda Zoghbi at Baylor College of Medicine in Houston, Texas, and their colleagues selectively deleted a gene encoding a key transcription factor, ATOH1, in cells from the body skin and foot pads of mice, where Merkel cells are normally found. Merkel cells were absent from these areas, and by testing the response of different nerve types the researchers found a “conspicuous loss” of a specific type of touch response.
Further work will be needed to determine whether the cells are sensory receptors or have some other role in touch.