"The team inactivated the gene responsible for producing the protein in mouse embryos that were around the halfway point of development, intending to investigate how this change affected the developing spinal cord.
Instead, they found something unexpected: one of the bioengineered embryos had two extra legs where its genitals should be."
Tgfbr1 (transforming growth factor-beta receptor type 1) plays a key role in controlling the formation of the external genitalia and hind limbs. According to the article,
"The researchers discovered that Tgfbr1 helps dictate whether these structures become either genitals or limbs. It does this, they realized,by altering the way that DNA folds in the structure’s cells. As a result, deactivation of the protein changes the expression of other genes – in this strange case, at least, that meant additional limbs and no genitalia.The identification of chromatin elements uniquely associated with hindlimb and GT [genital] fates might guide the search for the molecular signature that specifies hindlimb or GT development. The large number of elements in each group suggest that these signatures might be quite complex, likely involving the combined activity of several factors. Identification of those factors will be challenging, considering that in mammals enhancers are typically located far from the genes they regulate, which are often not even the closest transcription unit."
*It should be no surprise that the created genetics (and associated regulatory processes) of animal and human embryos are complex and if tinkered with will create disabling, harmful, or fatal consequences.
*God created each creature to be able to reproduce according to its kind, which necessitates that their embryos develop normally. Yes, because we live in a fallen world, there are harmful mutations which sometimes creep in, but these are very small percentages. When was the last time you saw a six-legged mouse (or squirrel or deer) in the wild?
Yes, God has woven “remarkable tissue plasticity” into embryonic development. But this has nothing to do with evolution, which was what the researchers were attempting to prove.
It does however have everything to do with God, the common Designer of all animal and human life."
AIG
O Lord, how manifold are Your works!
In wisdom have You made them all;
the earth is full of Your creatures.
Psalm 104:24