> Weird title, needs a comma after "risky", but I guess HN removes them while sanitizing
It would be grammatically incorrect in English to put a single comma there. A correct alternative would be to put a comma there and also change "that" to ", which" - ie, reading, "Controversial experiments, which could make bird flu more risky, to resume". The entire relative clause needs to be sandwiched with commas; putting a single one at the end is incorrect.
That said, the title as it stands is grammatically correct, although it is potentially ambiguous in meaning.
Other languages have different rules about comma usage, but this is how it works in English.
It would be grammatically incorrect in English to put a single comma there. A correct alternative would be to put a comma there and also change "that" to ", which" - ie, reading, "Controversial experiments, which could make bird flu more risky, to resume". The entire relative clause needs to be sandwiched with commas; putting a single one at the end is incorrect.
That said, the title as it stands is grammatically correct, although it is potentially ambiguous in meaning.
Other languages have different rules about comma usage, but this is how it works in English.