  In recent years, chain sequences and their perturbations have played a
significant role in characterising the orthogonal polynomials both on the real
line as well as on the unit circle. In this note, a particular disturbance of
the chain sequence related to orthogonal polynomials having their true interval
of orthogonality as a subset of $[0,\infty)$ is studied leading to an important
consequence related to the kernel polynomials. Such perturbations are shown to
be related to transformations of symmetric measures. An illustration using the
generalized Laguerre polynomials is also provided.
