SAN FRANCISCO — Even with the cryptocurrency markets in an extended slump, the most prominent venture capital firm in the sector is doubling down.

Andreessen Horowitz, the well-known firm that made early bets on Instagram and Reddit, said on Monday that it was creating a $300 million fund focused exclusively on projects inspired by the original virtual currency, Bitcoin. One of the leaders of the new fund will be the firm’s first female general partner, Kathryn Haun, a former federal prosecutor.

Last year, when Bitcoin and most other virtual currencies were gaining in value, most of the large venture capital firms began beefing up on cryptocurrency expertise and making investments.

Andreessen Horowitz was ahead of many of its peers. It was one of the first venture capital firms to begin dabbling in cryptocurrencies in 2013, when digital tokens were a fringe business.