Chimera DNA
“You are Not the Mother of Your Children”
Biology 1308
Instructor Childress
June 22, 2012
Introduction This unusual case is based on a true story of a woman named Lillian, whose children were almost taken from her because her DNA profile indicated that she was not the mother of her children. The test revealed each child shared half of their DNA markers with their father, but only twenty-five percent of their DNA matches their mother. Our team will attempt to determine why this mother’s DNA profile does not match her children’s profiles.
Hypothesis
How is it possible for a mother’s DNA not to match the DNA of her biological children?
1. The “mother” is actually the children’s aunt
2. The “mother” is a gestational surrogate
3. The “mother” is a chimera
Methods and Results
1. The “mother” is really the children’s aunt: Lillian stated that the DNA tests showed that about a quarter of each child’s DNA matched her DNA. By understanding the gene-inheritance process, we can expect a shared DNA from a close relative to be included in an offspring’s DNA. Under normal circumstances, we can anticipate that a child will inherit 50% DNA from their mother & father, 25% from grandparents, aunts & uncles and about 12.5% from first cousins (Smith, 2011). Since the paternity test showed only a quarter of Lillian’s DNA matched her off-spring, this could most likely support Lillian’s statement and the presumption that Lillian is actually their Aunt. However, this theory can be rejected due to the fact that Lillian does not have a biological sister to support this hypothesis.
2. The “mother” is a gestational surrogate: Lillian was also questioned whether she had undergone In Vitro Fertilization (IVF), or had acted as a surrogate mother for someone else. She denied both surrogate methods. This denial definitely had all the possibilities of being truthful due to the terms of the
Biology 1308
Instructor Childress
June 22, 2012
Introduction This unusual case is based on a true story of a woman named Lillian, whose children were almost taken from her because her DNA profile indicated that she was not the mother of her children. The test revealed each child shared half of their DNA markers with their father, but only twenty-five percent of their DNA matches their mother. Our team will attempt to determine why this mother’s DNA profile does not match her children’s profiles.
Hypothesis
How is it possible for a mother’s DNA not to match the DNA of her biological children?
1. The “mother” is actually the children’s aunt
2. The “mother” is a gestational surrogate
3. The “mother” is a chimera
Methods and Results
1. The “mother” is really the children’s aunt: Lillian stated that the DNA tests showed that about a quarter of each child’s DNA matched her DNA. By understanding the gene-inheritance process, we can expect a shared DNA from a close relative to be included in an offspring’s DNA. Under normal circumstances, we can anticipate that a child will inherit 50% DNA from their mother & father, 25% from grandparents, aunts & uncles and about 12.5% from first cousins (Smith, 2011). Since the paternity test showed only a quarter of Lillian’s DNA matched her off-spring, this could most likely support Lillian’s statement and the presumption that Lillian is actually their Aunt. However, this theory can be rejected due to the fact that Lillian does not have a biological sister to support this hypothesis.
2. The “mother” is a gestational surrogate: Lillian was also questioned whether she had undergone In Vitro Fertilization (IVF), or had acted as a surrogate mother for someone else. She denied both surrogate methods. This denial definitely had all the possibilities of being truthful due to the terms of the