Our ancestors can be detected not only in our genes, but also in our metabolism, a new study by Yale has found.
In an analysis of the metabolic profiles of healthy American children, researchers found striking differences between ethnic groups that can help make screening for inherited metabolic disorders, cystic fibrosis, or hypothyroidism much more accurate than traditional screenings of genetic diseases.
“We don’t want to lose a child who is potentially ill, and we don’t want to subject families to the burdens and worries that can result from a false positive test,” said Curt Scharfe, associate professor of genetics at Yale School of Medicine and senior author of the study. published in the journal Molecular Genetics and Metabolism.
For the study, Scharfe and colleagues analyzed data collected from more than 400,000 babies, representing 17 self-reported ethnic groups, who were part of the California newborn screening program. Specifically, they wanted to know if these ethnic differences could be detected in metabolites, molecules that provide energy by breaking down food or body tissues such as fat, found in the blood of children.
The question was not only of academic interest, it also worried pediatricians. For example, children of African descent are known to have higher blood biomarkers indicating cystic fibrosis than children born to white parents, although children born to white parents are much more likely to develop the disease. The researchers hope that using ancestry to interpret these differences in marker levels may offer more accurate ways to assess risks than traditional genetic testing.
It is also known that people of African descent have greater genetic diversity than those of ethnic groups because they are descendants of the oldest ancestral population in the world. Modern humans have migrated from Africa to regions around the planet; other ethnic groups are descendants of these original migrants and have enough variation in their DNA to make them genetically identifiable.
But metabolic lineages may tell a different story, the researchers found. For example, while there is a clear demarcation between genetic variants between African Americans and Americans of European descent, the researchers found that these two groups are metabolically more closely related. Conversely, while people of Japanese and Chinese descent, for example, are genetically closely related, the researchers found greater differences in their metabolic profiles.
“This attests to the role of the environment in the formation of our metabolism,” Scharfe said. “Where people share the same culture and food, metabolic profiles are more similar. Where people are separated by circumstances, such as language or lifestyle, the differences in metabolism are greater than genetic variations.”
Scharfe cautions that more work needs to be done before the results can be applied clinically. The researchers analyzed only 41 out of many hundreds of metabolites and relied on parental accounts of their ethnic heritage, which may not always match reality.
“This is just a first snapshot, but understanding our metabolic ancestry has a promising future,” Scharfe said.
Gang Peng, an associate researcher of biostatistics and bioinformatics in Yale’s departments of biostatistics and genetics, is the first author of the study.
Materials provided by Yale University. Original written by Bill Hathaway. Note: The content can be changed by style and length.