  Here we examine the evolution of beta-2 microglobulin in terms of its
hydropathic shapes, a theoretical construct that has revealed important trends.
The dynamics of many proteins are largely driven by interactions between the
protein itself and the thin water film that covers it. \b{eta}2m constitutes
the basic building unit of the immunoglobulin superfamily; the evolution of its
amino acid sequences from chickens to mice to humans provides new information
about its multiple functions. Our hydrodynamic method involves concepts of
topological shape evolution towards a critical point for optimized functions.
The results are in excellent agreement with experiment for the details of the
mouse-human evolution, as well as both the dangerous natural amyloid
aggregation mutation D76N, and six other DN test mutations.
