Generic function of indefinite article

"In 2002, a British chain of supermarkets announced a genetically modified carrot" - Does the article 'a' in this sentence have a generic function?

In "Practical English Usage" by M. Swan It is said: We can also generalise by talking about one example of a class, using a/an (meaning "any") with a singular countable noun - A baby deer can stand as soon as it's born

But you can't say here "In 2002, a British chain of supermarkets announced ANY genetically modified carrot" So is it generalisation or not?

Solution 1:

I'm pretty sure they were not announcing a single genetically modified carrot but the practice of stocking for sale a choice of carrots, genetically modified in addition to normal ones. The 'a' then is generic. But you're right, the use of 'Any' is not correct.

They could decide to not include any genetically modified carrots. The any would then be describing the exclusion of the set.