The Associated Press German scientists have provided the first direct evidence that a key enzyme's failure to mop up dying cells contributes to lupus, a potentially fatal immune disorder. The study, published in the June issue of the journal Nature Genetics, involved only mice. However, researchers said the immune reactions are very similar to what occur in humans. Lupus is a disorder that causes the body's own defenses to mistakenly attack the DNA and proteins within healthy cells. Complications include arthritis, blood vessel inflammations and kidney failure.
Scientists believe lupus is rooted in many subtle genetic abnormalities.
One of many suspected factors is a mutation that disrupts the body's waste disposal mechanism in cells. The researchers turned off the gene that encodes DNase1 in specially bred mice. The mice appeared healthy at birth. After six to eight months, up to 73 percent of the mice without the DNase1 gene were showing lupus symptoms. The study was led by researchers in laboratories in Essen and Bochum, Germany.