On the same day it was announced that Pinduoduo had overtaken Alibaba to become China’s largest e-commerce company according to the metric of annual active buyers, its founder and chairman, Colin Huang, stepped down.

Huang, who at 41 is one of the youngest members of the upper echelons of China’s rich lists, at number 7 in 2020 according to Forbes with a net worth in excess of $52 billion, is resigning as China’s powerful internet sector comes under growing government scrutiny.

In a letter to shareholders, Huang said he was stepping down to pursue personal interests in life sciences. He is in talks with Chinese universities to set up research labs on biotechnology, an unnamed source told The Wall Street Journal.

Chief executive, Chen Lei, who took over that role from Huang in July last year, will now take on the additional role of chairman of the Nasdaq-listed company.

In 2020, Pinduoduo had 788.4 million annual active buyers, up 35 percent from a year earlier. It marked the first time Shanghai-based Pinduoduo exceeded Alibaba’s 779 million annual active buyers.