The data revealed height had a genetic component related to Bantu ancestry: The more Bantu ancestry an individual from the Pygmy tribe had, the taller that individual tended to be. One part of the genome, on chromosome 3, was especially important in this trait, the researchers said.
“We kept seeing a lot of them [these single-letter differences] highlight that region in chromosome 3,” Tishkoff said. “It just seemed like a hot spot for selection and for very high differentiation and, as it turns out, very strong association with height as well.”
There’s been a long-standing debate about why Pygmies are so short and whether it is an adaptation to living in a tropical environment,” study researcher Sarah Tishkoff of the University of Pennsylvania said in a statement. “Our findings are telling us that the genetic basis of complex traits like height may be very different in globally diverse populations.