Mechanisms for phenotypic variation in Lesch–Nyhan disease and its variants - Radhika Sampat; Rong Fu; Laura E. Larovere; Rosa J. Torres; Irene Ceballos-Picot; Michel Fischbach; Raquel de Kremer; David J. Schretlen; Juan Garcia Puig; H. A. Jinnah (Human Genetics, 2011)