01 / The experiment
Can we change
pigmentation?
At LADE in Chile, I helped establish a CRISPR-Cas9 workflow in Xenopus frogs. Pigmentation gave us a visible readout: the injected larvae showed lighter pigmentation, with genetic confirmation still pending.
Choose a targetPrepare the guide RNAInject embryosObserve pigmentation
02 / Understand the target
Two copies.
One appears inactive.
X. laevis has two copies of the pigmentation gene Oca2, called L and S. I compared them with X. tropicalis. Three clues support the conclusion that the S copy has lost its function.
Expression: is the gene copied into RNA?
The inspected RNA data show a signal for the L copy, but no detectable signal for S. This is the first clue that S is inactive.
Faded blocks: no RNA signal detected for S
The sequence evidence
The report identifies insertions in exons 3 and 6, followed by deletions in exons 13 and 19. Together, these shift the reading frame over a large region. A separate, whole-exon deletion removes 141 DNA bases.
03 / From gene to protein
A missing piece
changes the protein.
A gene provides instructions for a protein. Oca2 has regions that cross a membrane. The deleted exon affects one of these regions—another reason the S copy is unlikely to produce a working protein.
The protein chain folds through the membrane. Each upright segment here represents a membrane-crossing region.
Explore the protein figure from the report
What I took from the project
Sequence analysis changed how we interpreted the target. The lab work established a workflow and revealed lighter pigmentation; genotyping and systematic scoring remained the next steps.
Read the full reportThe academic foundations