Feb 6 (Reuters) - Gene sequencing machine maker Illumina forecast 2025 revenue largely below Wall Street estimates on Thursday, signaling subdued demand for its genetic tests and diagnostic tools, sending shares down nearly 4% in extended trading.

Diagnostic tool makers such as Illumina have witnessed reduced spending from biotech clients in the past two years, but recent interest rate cuts could improve the funding environment for biotechs as borrowing costs might ease.

The company forecast annual revenue of $4.28 billion to $4.4 billion for 2025, the midpoint of which is below analysts' average estimate of $4.39 billion, according to data compiled by LSEG.

Illumina said its forecast does not attempt to reflect any impact from the recent China Ministry of Commerce announcement.

Earlier this week, China, which accounts for about 7% of Illumina's sales, placed the company on its "unreliable entity" list.

Companies added to the blacklist can be subject to fines and other sanctions, including a freeze on trade and a revocation of work permits for foreign staff.

Illumina had said it is "assessing the announcement with the goal of finding a positive resolution."

The San Diego, California-based company's revenue was $1.10 billion in the fourth quarter, above analysts' estimate of $1.08 billion.

On an adjusted basis, it earned 95 cents per share during the quarter ended December 29, while analysts, on average, expected 91 cents per share.