Scientists have proven that everyone descended from one ancestral mother, whom they call Mitochondrial Eve. This name is from a 1987 study that found all people were genetically linked to the same historical matriarch.
Basically, a person's body is made up of cells with a certain part of each cell called mitochondria. DNA in every other part of the cell comes from the father and mother. But DNA in the cell's mitochondria comes only from the mother. Essentially, each child's mitochondrial DNA matches their mother's.
The landmark study in 1987 found that all people have exactly the same mitochondrial DNA. Scientists uphold the study as proof that everybody comes from a single mother thus known as Mitochondrial Eve.
Science and Sacred Scripture are in perfect agreement. According to the Bible, Eve is the name Adam gave his wife, as Genesis 3:20 recounts, "because she was the mother of all the living." But having Eve as the original mother means that Adam is the biological father of all mankind including Eve as Genesis 2:21-23 attests that God made Eve's body from Adam's rib.
Catholics also have a spiritual reason for knowing each person shares a common ancestry. The Church teaches mankind inherits original sin from the head of the human race, Adam. This historical patriarch lost sanctifying grace by committing a mortal sin.
All of Adam's descendants, meaning humankind, would have shared in Adam's blessings without personally meriting it. So too they now share in his punishment without personally meriting it. As a result, all people are created in the state of original sin, meaning they are created without God's sanctifying presence in their souls.
Pope Pius XII in his 1950 encyclical Humani Generis flagged the unscientific theory that mankind has multiple first parents. The Pope noted this heresy, called "polygenism," contradicts the Catholic teaching that original sin "proceeds from a sin actually committed by an individual Adam and which, through generation, is passed on to all."
Rediscover our first parents in season one of Church Militant's Premium show Armor of God—The Creation and Fall of Man.