Two Cathie Wood funds are back in the spotlight after adding about $1 billion in market value on Monday following a promising advance in the field of gene editing.

Wood’s Ark Investment Management LLC is a top holder of companies operating in this area after the active investor made an early bet on Crispr Therapeutics AG, Intellia Therapeutics Inc. and Editas Medicine Inc.—three companies using a technology for editing the human genome called Crispr. Ark is also the second largest holder in Beam Therapeutics Inc., another company working on fixing genetic mutations.

All four stocks rallied after Intellia and Regeneron Pharmaceuticals Inc. produced the first study of a Crispr treatment to alter genes inside the body, driving up the stocks of gene editing and other biotechs working with therapies around human DNA. The move marks a rebound for Editas and Crispr, as well as a pair of Wood’s actively managed exchange traded funds, which were hammered earlier this year as investors turned away from more speculative growth stocks to value safe havens.

The Ark Genomic Revolution ETF rose 3.0% on Monday while the nearly $25 billion Ark Innovation ETF rallied 3.7% as of midday in New York.

“This may sway the FDA to be more constructive toward running gene editing trials in the U.S.,” said Benjamin Burnett an analyst with Stifel. Intellia’s trial was also a good sign for Precision BioSciences Inc., he told clients in a research note, and the stock climbed as much as 12%.

Intellia led the gains, soaring as much as 63% to a record in Monday trading, while Crispr climbed 10% at the high trade. Beam jumped as much as 21%. Editas gained as much as 20% before paring to a 4.8% gain.

Sentiment driven gains for Editas are “unwarranted” Goldman Sachs analyst Madhu Kumar told clients saying he saw a lack of similarities between sell-rated Editas and buy-rated Intellia’s technologies. The bank raised the 12-month price target on Intellia to $163 from $115.

Meanwhile, Alnylam Pharmaceuticals Inc. which works on a medicine to treat transthyretin amyloidosis—the disease Intellia is trying to cure in its study—dropped 5.8%. Intellia is already hard at work on its next target, hereditary angioedema. BioCryst Pharmaceuticals Inc. and KalVista Pharmaceuticals Inc., companies working on treatments for that disease also tumbled in Monday trading.

“We believe this data will enter the history books, signifying that in vivo gene editing and one-time cures are possible,” Ark analyst Ali Urman wrote after Intellia’s update. “The only question remaining is will it be durable?”

With assistance from Kristine Owram.

This article was provided by Bloomberg News.