It is common knowledge that lupus runs in families. In fact, primary relatives (siblings, parents, children) of a person with the condition have a three- to five-fold increased risk of developing the disease compared with the average person on the street. But until just the last decade, we haven’t known how increased risk of lupus could be inherited.
Figuring out how lupus runs in families has been complicated. Lupus is not like some genetic diseases carrying a high profile in the popular press. The phrase “genetic disease” might bring to mind hemophilia among the royal families of Europe, or the “boy in the bubble” with immune deficiency, or cystic fibrosis. In each of these cases, mutation of one or a few genes is the illness driver.
In contrast, for most cases in which lupus runs in families, alteration in more than one gene is likely behind the increased disease risk. Lupus is thus said to be “polygenic.” In fact, if risk of ...Continue Reading →