High-Bone-Mass Disease and LRP5

To the Editor: Boyden et al. (May 16, 2002, issue) 1 report cosegregation of a syndrome of high bone density, jaw enlargement, and torus palatinus with a missense mutation — a G-to-T substitution at position 512, encoding a glycine-to-valine substitution at amino acid residue 171 (G171V) — in the gene encoding low-density lipoprotein receptor–related protein 5 ( LRP5 ). This autosomal dominant condition seemed benign, enhancing skeletal mass without causing complications of osteopetrosis. Genealogic studies showed no relationship with the healthy kindred with high bone mass described in 1997 by Johnson et al. 2 and documented as having the identical LRP5 V171 . . .