In this work, we study some special hypergeometric functions in positive characteristic, introduced by D.S. Thakur. We shall establish functional relationships among them, and deduce, with the help of the function field version of the Schneider-Lang theorem obtained by J. Yu, that at least one of their values at nonzero algebraic arguments is transcendental. (C) 2019 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved.