Hidden Stories of Chinese Migration and Culture Found in Giant Genetic Study

Lamb stew, hearty and fragrant, cooked until meat falls off the bone and served alongside thick, chewy noodles — this is the type of food that cuts through northern China’s winter chill.

Further south, warmer climates support more crops. Fresh, stir-fried greens might accompany dim sum in Guangdong or punctuate a spicy meal in Sichuan. Lychee, durian and other fruits ripen the air.

Comb through the DNA of Chinese people and you’ll find a trace of this culinary story, according to the largest-scale genetic study of Chinese people to date, published Thursday in Cell. The authors reported that a mutation of FADS2, a gene involved in metabolizing fatty acids, is more common in northern than southern populations, indicating a diet richer in animal content. It is one of an assortment of findings resulting from a sweeping analysis of genetic information from 141,431 participants.

The approach — a novel one using data from prenatal blood tests — came with a trade-off. Though researchers were able to cheaply sequence a large number of genomes, they had access to a small...