Heritability of Innate Immune Inflammatory Responses

There are big differences in how people respond to severe bacterial infection.  The inflammatory response of white blood cells to harmful bacteria that invade the body may play an important role in determining how well a patient will be able to fight the infection. The purpose of this study was to better understand how genetic factors control the amount of inflammation of white blood cells when exposed to bacteria that cause serious diseases.  This is an important area of research and may eventually help in the development of new ways to diagnose and treat patients with severe infections.

This study recruited 226 healthy twin pairs.  A twin study was done because it is the ideal way to find out how genetic factors and environmental factors contribute to the way the body responds during a severe infection.

A small sample of blood (about 5 tablespoons) was drawn from each participant. In the laboratory, the blood was mixed with different bacteria in different test tubes, and measurements were made of the amount of inflammation that was produced.

DNA was collected from the blood sample, to see whether certain genes control the amount of inflammation in response to the bacteria. Some of the DNA was used to determine zygosity – whether the twin participants were identical (MZ) or fraternal (DZ). This information helps us make improvements to our self-report zygosity algorithm.

DNA Determination
MZ DZ IZ
Self Report Determination MZ 130 11 3
DZ 0 35 2
IZ 1 11 0