Australian dragons' gender determined by epigenetic differences

Reptiles' sex is determined by the shape of chromosomes

https://phys.org/news/2022-01-australian-dragons-gender-epigenetic-differences-1.html?fbclid=IwAR2Ew-NbGn-iyHiRa5GMwO4IW2yhoM36Vo0QoZNJ7UH2eUGMSiu5I7A24pc

Excerpts: "Published today in PNAS, the study showed dragon lizards are determined to be male or female by epigenetic rather than genetic differences—that is, changes in the gene's chromosomal neighborhood rather than the gene itself."

"Professor Graves said the research team were astounded by the discovery.

"We looked at the genes of the sex chromosomes in both sexes, and could find no DNA sequence that distinguished them from each other. We couldn't understand why they weren't acting in the same way," Professor Graves said.

"It was particularly odd, because the two sex chromosomes look quite different under the microscope. The female-specific (W) chromosome has lots of highly repetitive (junk) DNA that stains brightly.

"Our breakthrough was the realization that this repetitive DNA might distort the W chromosome so that the sex gene was read incorrectly," Professor Graves said.
"So rather than sex being determined by the base sequence of a sex gene—like in humans, and every other animal we know about—in the dragon lizard it was about the gene's kinky chromosomal 'neighborhood.'""

""We would never have discovered this unique way of doing genetic sex determination if we'd just looked at humans, mice and zebrafish! Peculiar species like dragon lizards can provide new information about genes and gene regulation," Professor Graves said."

https://www.pnas.org/content/119/4/e2116475119

"We propose that altered configuration of the repeat-laden W chromosome affects the conformation of the primary transcript to generate more diverse and potentially inhibitory W-borne isoforms that suppress testis determination. This is a mechanism for vertebrate sex determination, in which epigenetic control regulates the action of a gene present on both sex chromosomes."

My comment: Researchers are surprised again. Genetic determinism just got long nails in the coffin. DNA doesn't determine organismal traits or characteristics. Could blind evolution develop a mechanism in which 3D shape of chromosomes affects sex determination? Certainly not. This discovery also contradicts with evolutionary ideas concerning assumed evolutionary steps from fish to amphibians to reptiles etc. But from the point of view of design, this kind of dynamic feature is very useful for reptiles in challenging environments. Evolution never happened.