China announced a ban on Tuesday on imports of genetic sequencers from U.S. medical equipment maker Illumina just minutes after U.S. President Donald Trump’s additional 10% tariff on Chinese goods took effect.

The ban is part of a series of measures China announced in response to the extra U.S. tariffs and comes after Beijing put Illumina on its “unreliable entity” list in February.

China accounts for about 7% of Illumina’s sales. Gene sequencers help determine the sequence of DNA or RNA, allowing scientists to study genetic variations associated with diseases and diagnose rare genetic conditions.