Xing, ZZ (reprint author), CCAST, World Lab, POB 8730, Beijing 100080, Peoples R China.
We point out that the Cabibbo-Kobayashi-Maskawa (CKM) quark mixing matrix V-CKM and the Maki-Nakagawa-Sakata (MNS) lepton mixing matrix V-MNS can naturally be correlated in a class of seesaw models if the Dirac neutrino mass matrix and the up-type quark mass matrix are symmetric and identical, but the texture of their correlation matrix F-v is rather nontrivial. The bimaximal mixing pattern of F-v is disfavored by current data, and other special forms of F-v may suffer from fine-tuning of the free phase parameters in fitting the so-called quark-lepton complementarity relation. A straightforward calculation of F-v in terms of V-CKM and V-MNS reveals a striking feature of F-v: its (1, 3) element cannot be zero or too small, no matter whether the (1, 3) elements of V-CKM and V-MNS are vanishing or not. We also add some brief comments on possible radiative corrections to V-CKM and V-MNS. (c) 2005 Elsevier B.V. All rights reserved.