Today in the United States, health is one of the biggest concerns upon Americans. When it comes to the birth of a mother’s baby, families hope and pray that the newest member to the family is healthy. It was discovered that mitochondria DNA mutations were resulting in many birth defects, especially in older mothers. Recent studies from a team of Penn State scientists predicted that older mother was, the more likely she was to have a baby with a disease which can eventually contribute to other diseases such as diabetes, cancer, Parkinson’s disease and Alzheimer’s disease.
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As we have learned in chapter six, the mitochondria is said to be the “powerhouse” of the cell. It contains Mitochondrial DNA (in the mitochondrial matrix) and generates ATP (adenosine triphosphate) in the inner mitochondrial membrane. Mitochondria contain small circular DNA molecules that carry genes coding for proteins and RNA. These organelles reproduce themselves and transmit their genes to daughter cells. Mitochondrion is found in eukaryotic cells and is a double-membrane-bound organelle. Mitochondria are responsible for tasks like cell death, cell growth, the cell cycle and cellular differentiation. However, when there is a detected mitochondrion defect this often results in mitochondrial diseases.
“Mitochondrial diseases affect more than one system in the human body…they affect organs that require a lot of energy, including the heart, skeletal muscle, and brain. They are devastating diseases and there is no cure, so our findings about their transmission are very important.” states Kateryna Makova, professor of biology and one of the Penn State study’s primary investigators.
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Samples of blood as well as cheek cells were taken from healthy mothers ranging in the ages of 25-39 as well as their children to observe DNA sequencing and transmission in maternal egg cells. According to the results of the testing of these cells, the scientists found more mutations in the cells of older mothers. This could be predicted because as humans get older, cells continue to divide causing more mutant genes. Much of the genetic makeup is found in the mitochondria of a cell, which means the older the mother, the greater, the chance that her child could contract a mitochondrial disease.
According to the Penn State researchers, “Many mitochondrial diseases, 70 to 80 percent of molecules need to have the disease-causing variant for the disease to manifest itself. But for others, only 10 percent of the mtDNA molecules with the variant are needed to cause disease.” Mitochondrial diseases have also been defined by a lack of cellular energy due to oxidative phosphorylation.
In a childhood-onset disease there are often indications of developmental delay. However, mitochondrial diseases can be present at any age in life. Childhood mitochondrial diseases are usually more severe than adult mitochondrial diseases.
These studies are helping families plan properly for their futures. This is helping to understand the genetic concerns of several mitochondrial mutations to obtain correct knowledge of how one’s own genetics can affect future lives. When families are planning for children many now understand that it is better to have children at a younger age due to the mitochondrial mutations that can be transmitted at a later age to children before birth. The understanding of these mitochondrial mutations will help in the future with preventing severe diseases that can be diffused throughout families.