Through the looking glass

Proc. Natl Acad. Sci. USA (2014)

Age may bring wisdom, but it also tends to come with the inability to see things clearly — even when they're right in front of you. Presbyopia is a common condition involving progressive difficulty focusing on nearby objects, and it's associated with a hardening of the lens of the eye. Scattering data reported by Giuseppe Foffi and colleagues may hold the key as to why this is the case: their measurements are consistent with the appearance of a glassy arrested state in solutions of α-crystallin — a protein known to be abundant in the lens.

The transparency of the lens, which is crucial for clear vision, has previously been linked to short-range order between α-crystallin proteins. Foffi et al. found that their protein solutions were structurally liquid-like, consistent with a polydisperse hard-sphere model. And their dynamic light scattering and viscometry measurements pointed toward the existence of a glass transition, corroborated by molecular dynamics simulations and mode-coupling theory. The results suggest that the α-crystallin in our lenses may have a role in the onset of presbyopia.


Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Klopper, A. Through the looking glass. Nature Phys 10, 899 (2014).

Download citation