4Q33-QTER DELETION AND ABSORPTIVE HYPERCALCIURIA - REPORT OF 2 UNRELATED GIRLS

We report on two unrelated girls with multiple malformations, each of whom had a der(4)t(4;?)(q33;?) chromosome-an unbalanced translocation chromosome with deletion of the 4q33-qter segment and addition of a se gment of an unknown chromosome. One of the two girls had asymptomatic kidney stones. Both had excess urinary calcium excretion (0.53 and 0.8 4 mg/mg creatinine, respectively), exaggerated excretion on oral calci um load, and reduced but excessive excretion on restricted calcium int ake. The urinary calcium excretion of their parents was normal. Both g irls were thus diagnosed to have sporadic absorptive hypercalciuria, I t was deduced that the 4q33-qter segment contains the putative gene fo r absorptive hypercalciuria. (C) 1998 Wiley-Liss, Inc.