The developmental basis of fingerprint pattern formation and variation.

Glover, James D. and Sudderick, ZR and Shih, BB and Batho-Samblas, C and Charlton, L and Krause, AL and Anderson, C and Riddell, J and Balic, A and Li, J and Klika, V and Woolley, TE and Gaffney, EA and Corsinotti, A and Anderson, RA and Johnston, LJ and Brown, SJ and Wang, S and Chen, Y and Crichton, Michael and Headon, DJ (2023) The developmental basis of fingerprint pattern formation and variation. Cell. pp. 940-956. ISSN 0092-8674

Abstract

Fingerprints are complex and individually unique patterns in the skin. Established prenatally, the molecular and cellular mechanisms that guide fingerprint ridge formation and their intricate arrangements are unknown. Here we show that fingerprint ridges are epithelial structures that undergo a truncated hair follicle developmental program and fail to recruit a mesenchymal condensate. Their spatial pattern is established by a Turing reaction-diffusion system, based on signaling between EDAR, WNT, and antagonistic BMP pathways. These signals resolve epithelial growth into bands of focalized proliferation under a precociously differentiated suprabasal layer. Ridge formation occurs as a set of waves spreading from variable initiation sites defined by the local signaling environments and anatomical intricacies of the digit, with the propagation and meeting of these waves determining the type of pattern that forms. Relying on a dynamic patterning system triggered at spatially distinct sites generates the characteristic types and unending variation of human fingerprint patterns.