Oct. 4 (UPI) -- Researchers have identified previously unknown genetic causes of mitochondrial disease.
Researchers from Colorado, the United Kingdom, the Netherlands, Spain, Israel and Australia collaborated on a search for what causes mitochondrial disease, a group of disorders caused by dysfunctional mitochondria, the organelles that generate energy for almost every cell in the body. The DNA research was published Wednesday in the journal Nature Communications.
A 2015 study found that one in 4,300 newborns are affected by the genetic condition. There is no cure and affected children often sadly die in early infancy. Symptoms can include muscle weakness, blindness, deafness, seizures, learning disabilities, diabetes and heart and liver failure.
The organelles create the energy needed to sustain life and support organ function, and problems can lead to the failure of whole organ systems and can cause accumulation of lactic acid.
Increasing a nutritional compound would improve the function of the cells from these patients, serving as a promising way to identify new treatments, the researchers said.
"Increasing glutamine levels markedly improved function in cells, so treating with glutamine is a logical approach," Dr. Johan Van Hove, a professor of pediatrics at the Colorado University School of Medicine and senior author of the new study, told UPI. "We are using glutamine supplements for a different indication already, which has been safe. Since we are not aware of any living patients today, it has not yet been used."
Researchers led by the CU School of Medicine studied five families with infants who had cardiomyopathy and excess acid in their blood, which appears when the cell's energy-generating system malfunctions. Four lived in Finland and one in Colorado.
The conditions appeared prenatally or when the newborn was 2 to 5 months old. They all died before turning 7 months old.
Because of complex biochemistry and genetic differences between individuals, mitochondrial diseases are difficult to diagnose.
When studying patterns, the scientists looked closer at specific genes -- QRSL1, GATB and GATC -- and determined that mutations in those genes caused the lethal conditions.
Last month, researchers at Newcastle University in Britain also identified the first patients with a different inherited mutation, in the genetic building block NDUFA6, in three children in the United Kingdom and one in Germany.