Jan 30 (Reuters) - Tidal Financial Group and ZEGA Financial launched a new exchange-traded fund (ETF) designed to profit from future growth in the "Magnificent Seven" growth and technology companies that have come to dominate U.S. market indexes and returns.

The YieldMax Magnificent 7 Fund of Options Income ETFs will invest in seven existing YieldMax single-stock ETFs that employ covered call options strategies to deliver both capital gains and income on each of those technology giants: Apple Inc., Microsoft Corp, Alphabet Inc. , Meta Platforms Inc., Tesla Inc., Amazon.com Inc. and Nvidia Corp..

Roundhill Investments became the first ETF provider to launch a fund explicitly targeting the theme that has captured investor attention and imagination in November, re-branding and relaunching a mega-tech ETF as the Roundhill Magnificent Seven ETF.

Assets under management promptly ballooned from about $10 million to $73 million today, according to data from Morningstar Direct and Roundhill.

While the Standard & Poor's 500 index climbed 24% last year, the Nasdaq Composite Index - dominated by the Magnificent Seven - jumped 43%. The group itself had an average gain of more than 110%.

TrackInsight, a Paris-based firm that monitors the ETF industry, says that until recently, issuers preferred to launch funds tied to broader slices of the technology universe, such as the NYSE FANG+ Index.

"There's a saying, 'feed the ducks while they're quacking', and investors are clearly quacking for Mag 7 stocks," said Steve Sosnick, chief strategist at Interactive Brokers, a trading and market-making firm.

He said that Magnificent Seven funds were "extraordinarily narrow", and such themes were by their nature fleeting, so investors could face big losses if earnings disappoint.

The three firms to have reported quarterly earnings so far - Microsoft, Alphabet and Tesla - have fallen short of lofty expectations. Tesla CEO Elon Musk warned of "notably slower" sales growth, while shares of Microsoft and Alphabet struggled after both announced a surge in costs as well as revenues after the market close Tuesday. (Reporting by Suzanne McGee Editing by Tomasz Janowski)