For those who invested Nvidia stocks and if they continue like this, the returns will be astounding. It delivered a 10-year annualized return of 75.3% in sterling terms.

One FTSE250 investment trust that has benefited Baillie Gifford American Growth Fund. In the period from March 2018 to the end of 2025, investments in Nvidia increased 3.155%!

Given Baillie Gifford’s track record of discovering top growth stocks like Nvidia and Teslait is worth keeping an eye on what up-to-date shares he is buying. One up-to-date name in the US Growth Trust portfolio caught my attention.

Let’s take a closer look at this hidden company – which recently went public and is already one of the trust’s larger holdings – to see what all the fuss is about.

Stock

A billion against one (NASDAQ:BLLN) is a medical diagnostics company. The quantification template platform is the only patented technology capable of counting DNA molecules with exceptional precision at scale.

After digging deeper into the company, I see some attractive things here. For starters, BillionToOne operates in two rapidly growing diagnostics markets: non-invasive prenatal testing and cancer testing. The company estimates that its total addressable market is approximately $100 billion in the United States alone.

It’s encouraging to see the company capitalizing on this opportunity, with third-quarter revenue up 117% year-over-year to $83.5 million. It delivered 165,000 tests, an escalate of 52%.

Management forecasts revenues for 2026 at the level of USD 415-430 million, which would represent an escalate of 40-45%. Most of its revenue comes from prenatal testing, which detects diseases such as cystic fibrosis and sickle cell disease using only the mother’s blood, but cancer testing is growing rapidly.

Another positive is that the company doesn’t skimp on cash. For the full year, it expects to report positive operating profit with high gross margins of around 70%. So it can be a very high-margin business.

Finally, the company’s market capitalization is currently just $3.9 billion. Nowadays, that’s really not much. If it seizes the commercial opportunity, the company could become much larger.

After all, Nvidia’s market capitalization was roughly this size in 2013.

Our long-term goal is to build a category-defining, generational company and become a member of the S&P 500.
A billion to one

My first takeaways

Stepping back, I see a few things here that indicate BillionToOne could become a top growth stock. Unlike many early-stage growth companies, it already delivers high margins and sustainable profitability through 2026.

In addition, there is solid support from institutional investors and huge opportunities for international expansion. It is also working on tests to detect cancer early, which could become the most invigorating market of all.

However, it’s far too early to call this game a slam dunk winner, let alone credit it with Nvidia-like potential. There is a lot of competition in this space Health Guardian AND Nateraand I fear that a up-to-date breakthrough in diagnostics may threaten the company’s technology at some point.

Meanwhile, the price-to-sales multiplier is almost 10, so the current valuation already takes into account a significant escalate.

For now, I think he’s worth keeping an eye on. BillionToOne will release its fourth-quarter results in early March.