Some seem to be in a tizzy about that, according to Michael Le Page at New Scientist:
We’ve found out why a Mexican cavefish has no eyes – and the surprising answer is likely to be seized upon by those who think the standard view of evolution needs revising.
It was assumed that these fish became blind because mutations disabled key genes involved in eye development. This has been shown to be the case for some other underground species that have lost their eyes.
But Aniket Gore of the US’s National Institute of Child Health and Human Development and colleagues haven’t found any disabling changes in the DNA sequences of eye development genes in the cavefish.
Instead, the genes have been switched off by the addition of chemical tags called methyl groups. This is what is known as an epigenetic, rather than genetic, change.
Shuker is suspicious of some efforts to promote the idea of an “extended evolutionary synthesis”. He thinks some people are trying sneak religious ideas back into evolutionary theory.
“They are trying to allow organisms to have agency not controlled by genes,” he says. More.
We know that the ducts need cleaning in the evolutionary biology building when people think there are laws of evolution, in a strict sense, and that the Big Worry is that if a claim for Darwinism is better explained by epigenetics, the proponents of epigenetics will sneak in religious ideas…
Note: Eva Jablonka is quoted as supporting an epigenetic interpretation.
See also: From Biology Direct: Darwinism, now thoroughly detached from its historical roots as a falsifiable theory, “must be abandoned” (The author sounds serious.)
Epigenetic change: Lamarck, wake up, you’re wanted in the conference room!