The authors present data on the rate of mutation of the mitochondrial hypervariable region in Adélie penguins from the Antarctic and compare this to the rate of evolution estimated using serially preserved ancient remains.
Although adhesion to laminin has been implicated in muscular dystrophies where the attachment between muscle cells and tendons fails, no early developmental requirements for laminin in fast muscle morphogenesis have been shown until now.
These findings support the hypothesis that the hypermutable cell subpopulation underlies most stress-induced mutants, rather than a minority of them.