Early Cities Spurred Evolution of Immune System?
...As in cities today, the earliest towns helped expose their inhabitants to inordinate opportunities for infection—and today their descendants are stronger for it, a new study says.
It's basic evolutionary theory: People who survive infection stand a better chance of having children and passing along disease-resistant genes. So groups from regions where urbanization has existed for thousands of years should be more disease resistant.
The trick was finding proof.
To do so, study co-author Ian Barnes, a molecular paleobiologist at University College London, screened DNA samples from 17 groups long associated with particular regions of Europe, Asia, and Africa—for example Anatolian Turks and the southern Sudanese.
Barnes analyzed the DNA samples for a gene associated with resistance to tuberculosis (TB) and suspected of being associated with resistance to leprosy as well as to leishmaniasis, a reaction to sand fly bites, and to Kawasaki disease, a childhood ailment that involves inflamed blood vessels and can lead to heart disease....
Read entire article at National Geographic News
It's basic evolutionary theory: People who survive infection stand a better chance of having children and passing along disease-resistant genes. So groups from regions where urbanization has existed for thousands of years should be more disease resistant.
The trick was finding proof.
To do so, study co-author Ian Barnes, a molecular paleobiologist at University College London, screened DNA samples from 17 groups long associated with particular regions of Europe, Asia, and Africa—for example Anatolian Turks and the southern Sudanese.
Barnes analyzed the DNA samples for a gene associated with resistance to tuberculosis (TB) and suspected of being associated with resistance to leprosy as well as to leishmaniasis, a reaction to sand fly bites, and to Kawasaki disease, a childhood ailment that involves inflamed blood vessels and can lead to heart disease....