Human HMGB Family Genes encode abundant DNA-binding and bending HMG-Box Family proteins (with structure, rather than sequence, specificity) that play an architectural role in nucleoprotein assembly. They have two homologous DNA-binding HMG-box domains connected by a short basic linker to an acidic C-terminus that differs in length. Tail length may be the dominant factor mediating property differences among HMGB proteins and determines DNA-binding properties of the HMG boxes. The tail is essential for DNA-binding. (NCI) [ ]