Fascinating article. So much for “you are what your dna says crowd”
How can a paternity test suggest a mother is also her daughter’s father?
The answer to that medical mystery, sparked by a confusing paternity test result, is “When the genes of a vanished twin brother live on in the mother’s DNA.” The finding, which genetics experts reported earlier this month, suggests that such human “chimeras” — people with DNA from more than one embryo — could be more common than we thought.
“What is the frequency of this? We don’t really know,” said Juan Yunis of Colombia’s Instituto de Genética. Only about 20 confirmed cases are documented, he said: “Probably there are more. And it can have a profound effect on one’s life.”
In recent decades, DNA studies have opened a new view on the truly messy biology of human reproduction, which is not always as textbook-neat as health class images of a sperm meeting an egg and nine months later, a baby resulting. The opening weeks of human development during pregnancy see rapid cell development in embryos, all orchestrated by a genetic shuffle that sometimes takes a more complicated course. That leads to outcomes ranging from triplets to miscarriages (which are thought to result from DNA abnormalities in about half of all known cases). One of those curious paths might lead to chimerism, where in an unknown number of cases, genes from a “vanishing twin” end up mixed in with those of a surviving sibling. There’s usually few outward signs of the condition, leading it to fly under the medical radar.
www.grid.news
How can a paternity test suggest a mother is also her daughter’s father?
The answer to that medical mystery, sparked by a confusing paternity test result, is “When the genes of a vanished twin brother live on in the mother’s DNA.” The finding, which genetics experts reported earlier this month, suggests that such human “chimeras” — people with DNA from more than one embryo — could be more common than we thought.
“What is the frequency of this? We don’t really know,” said Juan Yunis of Colombia’s Instituto de Genética. Only about 20 confirmed cases are documented, he said: “Probably there are more. And it can have a profound effect on one’s life.”
In recent decades, DNA studies have opened a new view on the truly messy biology of human reproduction, which is not always as textbook-neat as health class images of a sperm meeting an egg and nine months later, a baby resulting. The opening weeks of human development during pregnancy see rapid cell development in embryos, all orchestrated by a genetic shuffle that sometimes takes a more complicated course. That leads to outcomes ranging from triplets to miscarriages (which are thought to result from DNA abnormalities in about half of all known cases). One of those curious paths might lead to chimerism, where in an unknown number of cases, genes from a “vanishing twin” end up mixed in with those of a surviving sibling. There’s usually few outward signs of the condition, leading it to fly under the medical radar.
DNA showed a mother was also her daughter’s uncle — how scientists solved this medical mystery
Why genetic detectives think you may have more aunts and uncles than you suspected at the holiday table.
www.grid.news
