A pair of genes determines the stripes and colors of butterflies, according
to two research papers published in the Proceedings of the National Academy
of Sciences.

In the first paper authored by Linlin Zhang and colleagues at Cornell
University, CRISPR-Cas9 was used to "break" the gene, which made the
butterflies wings black and white. The second study conducted by Cornell's
Anyi Mazo-Vargas and other researchers from various institutions, showed
that when the WntA gene is cut out with CRISPR-Cas9, stripe patterns
disappear.

The results show how single genes have such immense impact. They counter the
idea that control of complex traits such as butterfly color patterns would
involve multiple genes.

[news.cornell.edu]
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